feat: Add database indexes

supabase/migrations/20251103145605_902a7a97-2762-474e-b904-6693c53bc533.sql

@@ -0,0 +1,94 @@
+-- P0 #7: Performance Optimization - Database Indexes
+-- Creates indexes on confirmed high-frequency tables only
+-- Focuses on moderation queue performance (most critical)
+
+-- ============================================================================
+-- CONTENT SUBMISSIONS (CRITICAL - Moderation Queue Performance)
+-- ============================================================================
+
+-- Moderation queue sorting (most critical for performance)
+CREATE INDEX IF NOT EXISTS idx_submissions_queue 
+  ON content_submissions(status, created_at DESC) 
+  WHERE status IN ('pending', 'flagged');
+
+-- Lock management queries
+CREATE INDEX IF NOT EXISTS idx_submissions_locks 
+  ON content_submissions(assigned_to, locked_until) 
+  WHERE locked_until IS NOT NULL;
+
+-- Moderator workload queries
+CREATE INDEX IF NOT EXISTS idx_submissions_reviewer 
+  ON content_submissions(reviewer_id, status, reviewed_at DESC) 
+  WHERE reviewer_id IS NOT NULL;
+
+-- Submission type filtering
+CREATE INDEX IF NOT EXISTS idx_submissions_type_status 
+  ON content_submissions(submission_type, status, created_at DESC);
+
+-- User submissions lookup
+CREATE INDEX IF NOT EXISTS idx_submissions_user 
+  ON content_submissions(user_id, created_at DESC);
+
+-- ============================================================================
+-- SUBMISSION ITEMS (Dependency Resolution)
+-- ============================================================================
+
+-- Submission item lookups and status tracking
+CREATE INDEX IF NOT EXISTS idx_submission_items_submission 
+  ON submission_items(submission_id, status, order_index);
+
+-- Dependency chain resolution
+CREATE INDEX IF NOT EXISTS idx_submission_items_depends 
+  ON submission_items(depends_on) 
+  WHERE depends_on IS NOT NULL;
+
+-- Item type filtering
+CREATE INDEX IF NOT EXISTS idx_submission_items_type 
+  ON submission_items(item_type, status);
+
+-- ============================================================================
+-- USER PROFILES (Profile Lookups)
+-- ============================================================================
+
+-- Username lookups (case-insensitive for search)
+CREATE INDEX IF NOT EXISTS idx_profiles_username_lower 
+  ON profiles(LOWER(username));
+
+-- User ID lookup
+CREATE INDEX IF NOT EXISTS idx_profiles_user_id 
+  ON profiles(user_id);
+
+-- ============================================================================
+-- MODERATION AUDIT LOG (Admin Queries)
+-- ============================================================================
+
+-- Audit log by moderator
+CREATE INDEX IF NOT EXISTS idx_audit_log_moderator 
+  ON moderation_audit_log(moderator_id, created_at DESC);
+
+-- Audit log by submission
+CREATE INDEX IF NOT EXISTS idx_audit_log_submission 
+  ON moderation_audit_log(submission_id, created_at DESC) 
+  WHERE submission_id IS NOT NULL;
+
+-- Audit log by action type
+CREATE INDEX IF NOT EXISTS idx_audit_log_action 
+  ON moderation_audit_log(action, created_at DESC);
+
+-- ============================================================================
+-- CONTACT SUBMISSIONS (Contact Form Performance)
+-- ============================================================================
+
+-- Contact queue sorting
+CREATE INDEX IF NOT EXISTS idx_contact_status_created 
+  ON contact_submissions(status, created_at DESC);
+
+-- User contact history
+CREATE INDEX IF NOT EXISTS idx_contact_user 
+  ON contact_submissions(user_id, created_at DESC) 
+  WHERE user_id IS NOT NULL;
+
+-- Assigned tickets
+CREATE INDEX IF NOT EXISTS idx_contact_assigned 
+  ON contact_submissions(assigned_to, status) 
+  WHERE assigned_to IS NOT NULL;