Add SnapTrade brokerage integration with full trade history support (#737)

* Introduce SnapTrade integration with models, migrations, views, and activity processing logic.

* Refactor SnapTrade activities processing: improve activity fetching flow, handle pending states, and update UI elements for enhanced user feedback.

* Update Brakeman ignore file to include intentional redirect for SnapTrade OAuth portal.

* Refactor SnapTrade models, views, and processing logic: add currency extraction helper, improve pending state handling, optimize migration checks, and enhance user feedback in UI.

* Remove encryption for SnapTrade `snaptrade_user_id`, as it is an identifier, not a secret.

* Introduce `SnaptradeConnectionCleanupJob` to asynchronously handle SnapTrade connection cleanup and improve i18n for SnapTrade item status messages.

* Update SnapTrade encryption: make `snaptrade_user_secret` non-deterministic to enhance security.

---------

Signed-off-by: Juan José Mata <juanjo.mata@gmail.com>
Co-authored-by: luckyPipewrench <luckypipewrench@proton.me>
Co-authored-by: Juan José Mata <juanjo.mata@gmail.com>

app/models/concerns/sync_stats/collector.rb

@@ -105,6 +105,32 @@ module SyncStats
       holdings_stats
     end
 
+    # Collects trades statistics (investment activities like buy/sell).
+    #
+    # @param sync [Sync] The sync record to update
+    # @param account_ids [Array<String>] The account IDs to count trades for
+    # @param source [String] The trade source (e.g., "snaptrade", "plaid")
+    # @param window_start [Time, nil] Start of the sync window (defaults to sync.created_at or 30 minutes ago)
+    # @param window_end [Time, nil] End of the sync window (defaults to Time.current)
+    # @return [Hash] The trades stats that were collected
+    def collect_trades_stats(sync, account_ids:, source:, window_start: nil, window_end: nil)
+      return {} unless sync.respond_to?(:sync_stats)
+      return {} if account_ids.empty?
+
+      window_start ||= sync.created_at || 30.minutes.ago
+      window_end ||= Time.current
+
+      trade_scope = Entry.where(account_id: account_ids, source: source, entryable_type: "Trade")
+      trades_imported = trade_scope.where(created_at: window_start..window_end).count
+
+      trades_stats = {
+        "trades_imported" => trades_imported
+      }
+
+      merge_sync_stats(sync, trades_stats)
+      trades_stats
+    end
+
     # Collects health/error statistics.
     #
     # @param sync [Sync] The sync record to update