fix(goals): address AI review on PR #1798 (CodeRabbit + Codex)

Correctness:
- GoalPledge#matches? rejects outflows on transfer pledges so a +$200
  purchase no longer satisfies a $200 deposit pledge after .abs
- GoalsController#sync_linked_accounts! saves through the goal so
  currency/depository/family validations actually run on update
- AlreadyClaimedError replaces empty RecordInvalid in resolve_with! and
  reconciler rescues the dedicated class
- SweepExpiredGoalPledgesJob wraps each expire! in a per-record rescue
- Assistant::Function::CreateGoal disambiguates duplicate account names
  and returns an absolute URL via mailer host config
- Family#savings_inflow_velocity defensively scopes from the family's
  accounts (was Account.joins(:goal_accounts).where(goal_id: ...))
- GoalPledgesController#set_goal preloads linked_accounts + providers
  to drop the N+1 on any_connected_account?
- Stepper subtitle update walks to the enclosing dialog before
  querySelector so two stepper instances don't fight over one header
- categories/_form.html.erb data-action targets color-icon-picker, not
  the non-existent "category" controller

UX / visual:
- Projection chart drops preserveAspectRatio="none" and pins endDate at
  today for past-due goals so the today marker stays in-domain
- _color_picker / categories form swap non-standard border-1 for border
- Goals index search input uses ring-alpha-black-100 (was raw gray-500)

Refactors:
- Goal#header_summary extracts the multi-line ERB header block
- Goal#catch_up_delta_money sums open_pledges in SQL
- Goal#projection_summary uses I18n.l for the on-track month label
- Account#default_pledge_kind moves the manual/transfer decision out of
  GoalPledgesController
- GoalPledge::Reconciler iterates ordered (created_at, id) so first-claim
  wins is deterministic under non-sequential PKs
- Goals::FundingAccountsBreakdownComponent + Goals::AccountStackComponent
  use clamp(0..) instead of Float::INFINITY / [x, 0].max
- Goals::StatusPillComponent#label provides a titleize fallback
- Goal projection chart skips the redundant initial _draw and reuses
  the snapped point in the past branch (no double-bisect)
- Goal pledge preview drops maximumFractionDigits: 0 so USD/EUR show
  cents while JPY/KRW stay whole-unit
- Demo generator captures the Wedding fund goal in the seed loop
  instead of looking it up by hardcoded name

Tests:
- GoalPledgeTest: outflow rejection
- GoalsControllerTest: cross-currency attachment rejected on update
- SweepExpiredGoalPledgesJobTest: cancelled coverage + per-record rescue
- GoalTest: pledge_action_label_key flips to manual_save without an
  unconditional guard

app/models/assistant/function/create_goal.rb

@@ -82,8 +82,8 @@ class Assistant::Function::CreateGoal < Assistant::Function
       )
     end
 
-    matched = family.accounts.where(accountable_type: "Depository").visible.where(name: linked_account_names).to_a
-    missing = linked_account_names - matched.map(&:name)
+    available = family.accounts.where(accountable_type: "Depository").visible.where(name: linked_account_names)
+    missing = linked_account_names - available.pluck(:name).uniq
     if missing.any?
       return error(
         "unknown_accounts",
@@ -93,6 +93,22 @@ class Assistant::Function::CreateGoal < Assistant::Function
       )
     end
 
+    # Multiple accounts can share a name. Block silent over-linking by
+    # surfacing the ambiguity so the assistant re-asks with disambiguated
+    # input rather than attaching every same-named account to the goal.
+    grouped = available.group_by(&:name)
+    ambiguous_names = grouped.select { |_, accts| accts.size > 1 }.keys
+    if ambiguous_names.any?
+      return error(
+        "ambiguous_accounts",
+        "Multiple accounts share a name. Ask the user which one to use.",
+        ambiguous_names: ambiguous_names,
+        available_accounts: depository_account_payload
+      )
+    end
+
+    matched = linked_account_names.map { |name| grouped[name].first }
+
     currencies = matched.map(&:currency).uniq
     if currencies.size > 1
       return error(
@@ -122,15 +138,28 @@ class Assistant::Function::CreateGoal < Assistant::Function
       target_amount_formatted: goal.target_amount_money.format,
       currency: goal.currency,
       target_date: goal.target_date&.iso8601,
-      url: Rails.application.routes.url_helpers.goal_path(goal),
+      url: absolute_url_for(goal),
       linked_account_names: matched.map(&:name),
-      message: "Created goal '#{goal.name}' (target #{goal.target_amount_money.format}). View it at #{Rails.application.routes.url_helpers.goal_path(goal)}."
+      message: "Created goal '#{goal.name}' (target #{goal.target_amount_money.format}). View it at #{absolute_url_for(goal)}."
     }
   rescue ActiveRecord::RecordInvalid => e
     error("validation_failed", e.record.errors.full_messages.join("; "))
   end
 
   private
+    # Build an absolute URL for the new goal so chat clients (which render
+    # outside the request that produced the goal) can link directly. Falls
+    # back to the relative path when no host is configured (e.g. self-hosted
+    # in a job without ENV).
+    def absolute_url_for(goal)
+      host_opts = Rails.application.config.action_mailer.default_url_options || {}
+      if host_opts[:host].present?
+        Rails.application.routes.url_helpers.goal_url(goal, host_opts)
+      else
+        Rails.application.routes.url_helpers.goal_path(goal)
+      end
+    end
+
     def parse_decimal(value)
       return nil if value.nil?
       BigDecimal(value.to_s)