Add parent/child category hierarchy to all category selects; add search to account select

Category selection consistency:
- DS::Select (shared component powering the main transaction form,
  transaction edit, bulk-update, and transfer category pickers) now
  indents subcategories with a corner-down-right icon, matching the
  existing transaction-row category dropdown.
- Feed DS::Select-based category pickers with Category.alphabetically_by_hierarchy
  (parent name, then parent-before-children, then own name) so children
  render directly under their parent.
- Added Category::Group.select_options, a shared helper producing
  parent-then-child ordered options (with an indent marker) for plain
  HTML <select> elements. Used by:
  - Rule builder category condition/action selects
  - Bulk 'categorize transactions' select
  - CSV/QIF import category mapping select
- Grouped the splits category combobox and the transaction search
  category filter checklist the same way, both with the
  corner-down-right indent icon used elsewhere.

Account selection:
- Added searchable: true to the account select in the new/edit
  transaction form, matching the category and merchant selects next
  to it.

app/components/DS/select.html.erb

@@ -50,6 +50,7 @@
       <% items.each do |item| %>
         <% is_selected = item[:value] == selected_value %>
         <% obj = item[:object] %>
+        <% is_child = obj&.respond_to?(:parent_id) && obj.parent_id.present? %>
 
         <%# Options use tabindex="-1" always — keyboard focus is managed
             programmatically so listbox items never appear in the Tab
@@ -67,6 +68,10 @@
             <%= helpers.icon("check") %>
           </span>
 
+          <% if is_child %>
+            <%= helpers.icon("corner-down-right", size: "sm") %>
+          <% end %>
+
           <% case variant %>
           <% when :simple %>
             <%= item[:label] %>

app/controllers/transactions_controller.rb

@@ -498,7 +498,7 @@ class TransactionsController < ApplicationController
         .alphabetically
         .includes(:account_providers, logo_attachment: :blob)
         .to_a
-      @categories = Current.family.categories.alphabetically.to_a
+      @categories = Current.family.categories.alphabetically_by_hierarchy.to_a
       @merchants = Current.family.available_merchants_for(Current.user).alphabetically.to_a
       @tags = Current.family.tags.alphabetically.to_a
     end

app/controllers/transfers_controller.rb

@@ -10,7 +10,7 @@ class TransfersController < ApplicationController
   end
 
   def show
-    @categories = Current.family.categories.alphabetically
+    @categories = Current.family.categories.alphabetically_by_hierarchy
 
     # Whether the current user can hit `mark_as_recurring`: feature flag on,
     # AND they have write access to BOTH transfer endpoints. Gating the

app/helpers/categories_helper.rb

@@ -20,6 +20,6 @@ module CategoriesHelper
   end
 
   def family_categories
-    [ Category.uncategorized ].concat(Current.family.categories.alphabetically)
+    [ Category.uncategorized ].concat(Current.family.categories.alphabetically_by_hierarchy)
   end
 end

app/models/category.rb

@@ -130,6 +130,17 @@ class Category < ApplicationRecord
       end
     end
 
+    # Builds [label, id] pairs for plain HTML <select> elements, ordered
+    # parent-then-children with children visually indented. Native <select>
+    # options can't render icons, so we use a unicode arrow prefix (regular
+    # leading spaces collapse in <option> text).
+    def self.select_options(categories)
+      for(categories).flat_map do |group|
+        [ [ group.category.name, group.category.id ] ] +
+          group.subcategories.map { |sub| [ "↳ #{sub.name}", sub.id ] }
+      end
+    end
+
     def initialize(category, subcategories = nil)
       @category = category
       @subcategories = subcategories || []

app/models/import/category_mapping.rb

@@ -25,7 +25,7 @@ class Import::CategoryMapping < Import::Mapping
   end
 
   def selectable_values
-    family_categories = import.family.categories.alphabetically.map { |category| [ category.name, category.id ] }
+    family_categories = Category::Group.select_options(import.family.categories)
 
     unless key.blank?
       family_categories.unshift [ "Add as new category", CREATE_NEW_KEY ]

app/models/rule/action_executor/set_transaction_category.rb

@@ -4,7 +4,7 @@ class Rule::ActionExecutor::SetTransactionCategory < Rule::ActionExecutor
   end
 
   def options
-    family.categories.alphabetically.pluck(:name, :id)
+    Category::Group.select_options(family.categories)
   end
 
   def execute(transaction_scope, value: nil, ignore_attribute_locks: false, rule_run: nil)

app/models/rule/condition_filter/transaction_category.rb

@@ -4,7 +4,7 @@ class Rule::ConditionFilter::TransactionCategory < Rule::ConditionFilter
   end
 
   def options
-    family.categories.alphabetically.pluck(:name, :id)
+    Category::Group.select_options(family.categories)
   end
 
   def prepare(scope)

app/views/splits/_category_select.html.erb

@@ -59,29 +59,35 @@
         <%= t("splits.new.uncategorized") %>
       </div>
 
-      <% categories.each do |category| %>
-        <% is_selected = category.id == selected_id %>
-        <% hex_color = category.color.presence || default_color %>
-        <div class="filterable-item text-sm cursor-pointer flex items-center gap-2 px-3 py-2 rounded-lg hover:bg-container-inset-hover <%= "bg-container-inset" if is_selected %>"
-             role="option"
-             tabindex="0"
-             aria-selected="<%= is_selected %>"
-             data-action="click->select#select"
-             data-value="<%= category.id %>"
-             data-filter-name="<%= category.display_name %>">
-          <span class="check-icon <%= "hidden" unless is_selected %>">
-            <%= icon("check") %>
-          </span>
-          <span class="flex items-center gap-2 text-sm font-medium rounded-full px-3 py-1 border truncate"
-                style="background-color: color-mix(in oklab, <%= hex_color %> 10%, transparent); border-color: color-mix(in oklab, <%= hex_color %> 20%, transparent); color: <%= hex_color %>;">
-            <% if category.lucide_icon.present? %>
-              <%= icon category.lucide_icon, size: "sm", color: "current" %>
-            <% else %>
-              <span class="size-1.5 rounded-full" style="background-color: <%= hex_color %>;"></span>
+      <% Category::Group.for(categories).each do |group| %>
+        <% [ group.category, *group.subcategories ].each do |category| %>
+          <% is_child = category.parent_id.present? %>
+          <% is_selected = category.id == selected_id %>
+          <% hex_color = category.color.presence || default_color %>
+          <div class="filterable-item text-sm cursor-pointer flex items-center gap-2 px-3 py-2 rounded-lg hover:bg-container-inset-hover <%= "bg-container-inset" if is_selected %>"
+               role="option"
+               tabindex="0"
+               aria-selected="<%= is_selected %>"
+               data-action="click->select#select"
+               data-value="<%= category.id %>"
+               data-filter-name="<%= category.display_name %>">
+            <span class="check-icon <%= "hidden" unless is_selected %>">
+              <%= icon("check") %>
+            </span>
+            <% if is_child %>
+              <%= icon("corner-down-right", size: "sm") %>
             <% end %>
-            <%= category.display_name %>
-          </span>
-        </div>
+            <span class="flex items-center gap-2 text-sm font-medium rounded-full px-3 py-1 border truncate"
+                  style="background-color: color-mix(in oklab, <%= hex_color %> 10%, transparent); border-color: color-mix(in oklab, <%= hex_color %> 20%, transparent); color: <%= hex_color %>;">
+              <% if category.lucide_icon.present? %>
+                <%= icon category.lucide_icon, size: "sm", color: "current" %>
+              <% else %>
+                <span class="size-1.5 rounded-full" style="background-color: <%= hex_color %>;"></span>
+              <% end %>
+              <%= category.display_name %>
+            </span>
+          </div>
+        <% end %>
       <% end %>
     </div>
   </div>

app/views/transactions/_form.html.erb

@@ -18,7 +18,7 @@
     <% if @entry.account_id %>
       <%= f.hidden_field :account_id, data: { transaction_form_target: "account" } %>
     <% else %>
-      <%= f.collection_select :account_id, manual_accounts, :id, :name, { prompt: t(".account_prompt"), label: t(".account"), selected: Current.user.default_account_for_transactions&.id, variant: :logo }, required: true, class: "form-field__input text-ellipsis", data: { transaction_form_target: "account", action: "change->transaction-form#checkCurrencyDifference" } %>
+      <%= f.collection_select :account_id, manual_accounts, :id, :name, { prompt: t(".account_prompt"), label: t(".account"), selected: Current.user.default_account_for_transactions&.id, variant: :logo, searchable: true }, required: true, class: "form-field__input text-ellipsis", data: { transaction_form_target: "account", action: "change->transaction-form#checkCurrencyDifference" } %>
     <% end %>
 
     <%= f.money_field :amount,

app/views/transactions/bulk_updates/new.html.erb

@@ -11,7 +11,7 @@
         <%= render DS::Disclosure.new(title: t(".transactions_section"), open: true) do %>
           <div class="space-y-2">
             <%= form.text_field :name, label: t(".name_label"), placeholder: t(".name_placeholder") %>
-            <%= form.collection_select :category_id, Current.family.categories.alphabetically, :id, :name, { prompt: t(".category_prompt"), label: t(".category_label"), class: "text-subdued", variant: :badge, searchable: true } %>
+            <%= form.collection_select :category_id, Current.family.categories.alphabetically_by_hierarchy, :id, :name, { prompt: t(".category_prompt"), label: t(".category_label"), class: "text-subdued", variant: :badge, searchable: true } %>
             <%= form.collection_select :merchant_id, Current.family.available_merchants_for(Current.user).alphabetically, :id, :name, { prompt: t(".merchant_prompt"), label: t(".merchant_label"), class: "text-subdued" } %>
             <%= form.select :tag_ids, Current.family.tags.alphabetically.pluck(:name, :id), { include_blank: t(".none"), multiple: true, label: t(".tags_label"), include_hidden: false } %>
             <%= form.text_area :notes, label: t(".notes_label"), placeholder: t(".notes_placeholder"), rows: 5 %>

app/views/transactions/categorizes/_entry_row.html.erb

@@ -11,7 +11,7 @@
       <%= format_money(entry.amount_money.abs) %>
     </span>
     <%= select_tag "category_id",
-          options_from_collection_for_select(categories, :id, :name),
+          options_for_select(Category::Group.select_options(categories)),
           prompt: t("transactions.categorizes.show.assign_category_prompt"),
           aria: { label: t("transactions.categorizes.entry_row.assign_category_select", name: entry.name) },
           class: "w-full text-xs border border-primary rounded-lg px-1.5 py-0.5 bg-container text-secondary",

app/views/transactions/searches/filters/_category_filter.html.erb

@@ -11,7 +11,8 @@
       ) %>
   <div class="my-2" id="list" data-list-filter-target="list">
     <% family_categories.each do |category| %>
-      <div class="filterable-item flex items-center gap-2 p-2" data-filter-name="<%= category.display_name %>">
+      <% is_child = category.parent_id.present? %>
+      <div class="filterable-item flex items-center gap-2 p-2 <%= "pl-6" if is_child %>" data-filter-name="<%= category.display_name %>">
         <%= form.check_box :categories,
                            {
                              multiple: true,
@@ -21,6 +22,9 @@
                            category.name,
                            nil %>
         <%= form.label :categories, category.display_name, value: category.name, class: "text-sm text-primary cursor-pointer" do %>
+          <% if is_child %>
+            <%= icon("corner-down-right", size: "sm") %>
+          <% end %>
           <%= render partial: "categories/badge", locals: { category: category } %>
         <% end %>
       </div>

app/views/transactions/show.html.erb

@@ -84,7 +84,7 @@
             </div>
             <%= f.fields_for :entryable do |ef| %>
               <%= ef.collection_select :category_id,
-                      Current.family.categories.alphabetically,
+                      Current.family.categories.alphabetically_by_hierarchy,
                     :id, :name,
                     { label: t(".category_label"),
                       class: "text-subdued", include_blank: t(".uncategorized"),

app/views/transfers/show.html.erb

@@ -84,7 +84,7 @@
       <%= styled_form_with model: @transfer,
               data: { controller: "auto-submit-form" }, class: "space-y-2" do |f| %>
         <% if @transfer.categorizable? %>
-          <%= f.collection_select :category_id, @categories.alphabetically, :id, :name, { label: t(".category"), include_blank: t(".uncategorized"), selected: @transfer.outflow_transaction.category&.id, variant: :badge, searchable: true }, "data-auto-submit-form-target": "auto" %>
+          <%= f.collection_select :category_id, @categories, :id, :name, { label: t(".category"), include_blank: t(".uncategorized"), selected: @transfer.outflow_transaction.category&.id, variant: :badge, searchable: true }, "data-auto-submit-form-target": "auto" %>
         <% end %>
         <%= f.text_area :notes,
                   label: t(".note_label"),