feat: Exclude approved forms from drafts list

Added filtering to exclude approved/confirmed forms from drafts list:
- Updated /drafts/list endpoint to filter out forms with status_code='approved' or is_confirmed=true
- Created SQL script for n8n to mark forms as approved after processing Redis channel data
- Forms marked as approved will no longer appear in drafts list

SQL script: SQL_MARK_FORM_APPROVED.sql
- Updates status_code to 'approved'
- Sets is_confirmed = true
- Uses claim_lookup CTE to find claim by id or payload->>'claim_id'

Files:
- backend/app/api/claims.py (updated drafts list queries)
- docs/SQL_MARK_FORM_APPROVED.sql (new SQL script for n8n)

backend/app/api/claims.py

@@ -201,6 +201,8 @@ async def list_drafts(
                 c.updated_at
             FROM clpr_claims c
             WHERE c.unified_id = $1
+              AND (c.status_code != 'approved' OR c.status_code IS NULL)
+              AND (c.is_confirmed IS NULL OR c.is_confirmed = false)
             ORDER BY c.updated_at DESC
             LIMIT 20
             """
@@ -227,6 +229,8 @@ async def list_drafts(
                   AND ua.channel_user_id = $1
                 LIMIT 1
             )
+              AND (c.status_code != 'approved' OR c.status_code IS NULL)
+              AND (c.is_confirmed IS NULL OR c.is_confirmed = false)
             ORDER BY c.updated_at DESC
             LIMIT 20
             """
@@ -246,6 +250,8 @@ async def list_drafts(
                 c.updated_at
             FROM clpr_claims c
             WHERE c.session_token = $1
+              AND (c.status_code != 'approved' OR c.status_code IS NULL)
+              AND (c.is_confirmed IS NULL OR c.is_confirmed = false)
             ORDER BY c.updated_at DESC
             LIMIT 20
             """