Harden SimpleFin sync: retries, safer imports, manual relinking, and data-quality reconciliation (#544)

* Add tests and enhance logic for SimpleFin account synchronization and reconciliation

- Added retry logic with exponential backoff for network errors in `Provider::Simplefin`.
- Introduced tests to verify retry functionality and error handling for rate-limit, server errors, and stale data.
- Updated `SimplefinItem` to detect stale sync status and reconciliation issues.
- Enhanced UI to display stale sync warnings and data integrity notices.
- Improved SimpleFin account matching during updates with multi-tier strategy (ID, fingerprint, fuzzy match).
- Added transaction reconciliation logic to detect data gaps, transaction count drops, and duplicate transaction IDs.

* Introduce `SimplefinConnectionUpdateJob` for asynchronous SimpleFin connection updates

- Moved SimpleFin connection update logic to `SimplefinConnectionUpdateJob` to improve response times by offloading network retries, data fetching, and reconciliation tasks.
- Enhanced SimpleFin account matching with a multi-tier strategy (ID, fingerprint, fuzzy name match).
- Added retry logic and bounded latency for token claim requests in `Provider::Simplefin`.
- Updated tests to cover the new job flow and ensure correct account reconciliation during updates.

* Remove unused SimpleFin account matching logic and improve error handling in `SimplefinConnectionUpdateJob`

- Deleted the multi-tier account matching logic from `SimplefinItemsController` as it is no longer used.
- Enhanced error handling in `SimplefinConnectionUpdateJob` to gracefully handle import failures, ensuring orphaned items can be manually resolved.
- Updated job flow to conditionally set item status based on the success of import operations.

* Fix SimpleFin sync: check both legacy FK and AccountProvider for linked accounts

* Add crypto, checking, savings, and cash account detection; refine subtype selection and linking

- Enhanced `Simplefin::AccountTypeMapper` to include detection for crypto, checking, savings, and standalone cash accounts.
- Improved subtype selection UI with validation and warning indicators for missing selections.
- Updated SimpleFin account linking to handle both legacy FK and `AccountProvider` associations consistently.
- Refined job flow and importer logic for better handling of linked accounts and subtype inference.

* Improve `SimplefinConnectionUpdateJob` and holdings processing logic

- Fixed race condition in `SimplefinConnectionUpdateJob` by moving `destroy_later` calls outside of transactions.
- Updated fuzzy name match logic to use Levenshtein distance for better accuracy.
- Enhanced synthetic ticker generation in holdings processor with hash suffix for uniqueness.

* Refine SimpleFin entry processing logic and ensure `extra` data persistence

- Simplified pending flag determination to rely solely on provider-supplied values.
- Fixed potential stale values in `extra` by ensuring deep merge overwrite with `entry.transaction.save!`.

* Replace hardcoded fallback transaction description with localized string

* Refine pending flag logic in SimpleFin processor tests

- Adjust test to prevent falsely inferring pending status from missing posted dates.
- Ensure provider explicitly sets pending flag for transactions.

* Add `has_many :holdings` association to `AccountProvider` with `dependent: :nullify`

---------

Co-authored-by: Josh Waldrep <joshua.waldrep5+github@gmail.com>

app/views/simplefin_items/setup_accounts.html.erb

@@ -39,27 +39,31 @@
           </div>
         </div>
 
-        <!-- Sync Date Range Selection -->
+        <!-- Sync Data Information -->
         <div class="bg-surface border border-primary p-4 rounded-lg">
           <div class="flex items-start gap-3">
-            <%= icon "calendar", size: "sm", class: "text-primary mt-0.5 flex-shrink-0" %>
+            <%= icon "clock", size: "sm", class: "text-primary mt-0.5 flex-shrink-0" %>
             <div class="flex-1">
-              <p class="text-sm text-primary mb-3">
-                <strong>Historical Data Range:</strong>
+              <p class="text-sm text-primary mb-2">
+                <strong>Transaction History:</strong>
+              </p>
+              <p class="text-xs text-secondary">
+                SimpleFin typically provides <strong>60-90 days</strong> of transaction history, depending on your bank.
+                After initial setup, new transactions will sync automatically going forward.
+                Historical data availability varies by institution and account type.
               </p>
-              <%= form.date_field :sync_start_date,
-                    label: "Start syncing transactions from:",
-                    value: @simplefin_item.sync_start_date || 1.year.ago.to_date,
-                    min: 3.years.ago.to_date,
-                    max: Date.current,
-                    class: "w-full max-w-xs",
-                    help_text: "Select how far back you want to sync transaction history. Maximum 3 years of history available." %>
             </div>
           </div>
         </div>
 
         <% @simplefin_accounts.each do |simplefin_account| %>
-          <div class="border border-primary rounded-lg p-4">
+          <% inferred = @inferred_map[simplefin_account.id] || {} %>
+          <% selected_type = inferred[:confidence] == :high ? inferred[:type] : "skip" %>
+          <%# Check if this account needs user attention (type selected but subtype missing) %>
+          <% types_with_subtypes = %w[Depository Investment Loan] %>
+          <% needs_subtype_attention = selected_type != "skip" && types_with_subtypes.include?(selected_type) && inferred[:subtype].blank? %>
+
+          <div class="rounded-lg p-4 <%= needs_subtype_attention ? "border-2 border-warning bg-warning/5" : "border border-primary" %>">
             <div class="flex items-center justify-between mb-3">
               <div>
                 <h3 class="font-medium text-primary">
@@ -78,8 +82,6 @@
               <div>
                 <%= label_tag "account_types[#{simplefin_account.id}]", "Account Type:",
                              class: "block text-sm font-medium text-primary mb-2" %>
-                <% inferred = @inferred_map[simplefin_account.id] || {} %>
-                <% selected_type = inferred[:confidence] == :high ? inferred[:type] : "skip" %>
                 <%= select_tag "account_types[#{simplefin_account.id}]",
                               options_for_select(@account_type_options, selected_type),
                               { class: "appearance-none bg-container border border-primary rounded-md px-3 py-2 text-sm leading-6 text-primary focus:border-primary focus:ring-1 focus:ring-primary focus:outline-none w-full",