refactor

specs/019-superset-ux-redesign/contracts/modules.md

@@ -353,6 +353,7 @@ export const activityStore = derived(
 <!-- @UX_FEEDBACK: Mapped % column shows progress bar + percentage text -->
 <!-- @UX_FEEDBACK: Tables column shows count of SQL tables extracted -->
 <!-- @UX_FEEDBACK: Columns column shows "X/Y" format (mapped/total) -->
+<!-- @UX_FEEDBACK: Start Mapping button is disabled until valid source is configured -->
 <!-- @UX_RECOVERY: Failed mapping shows error toast with "Retry" action -->
 
 <!-- @PRE: User has permission plugin:mapper:execute for Map Columns -->

specs/019-superset-ux-redesign/tasks.md

@@ -249,8 +249,8 @@ All implementation tasks MUST follow the Design-by-Contract specifications:
 - [x] T062 [US4] Implement pagination controls with page numbers and "Rows per page" dropdown
 - [x] T063 [US4] Create floating bulk action panel at bottom: "[✓ N selected] [Map Columns] [Generate Docs] [Validate]"  
   _Contract: @UX_STATE: Selecting, @UX_FEEDBACK: Floating panel slides up_
-- [x] T064 [US4] Implement Column Mapping modal with PostgreSQL comments/XLSX source selection and preview  
-  _Contract: @POST: Map Columns modal shows source selection (PostgreSQL or XLSX)_
+- [x] T064 [US4] Implement Column Mapping modal with PostgreSQL comments/XLSX source selection and preview
+  _Contract: @POST: Map Columns modal shows source selection (PostgreSQL or XLSX) with validation_
 - [x] T065 [US4] Implement Documentation Generation modal with LLM provider selection and options  
   _Contract: @POST: Generate Docs modal shows LLM provider selection_
 - [x] T066 [US4] Create dataset detail view showing SQL tables, column counts, mapping percentages, and linked dashboards