chore: PostgreSQL migration compatibility and infrastructure improvements

Database & Migrations:
- Update all Alembic migrations for PostgreSQL compatibility
- Remove SQLite-specific syntax (AUTOINCREMENT, etc.)
- Add database utility helpers for PostgreSQL operations
- Fix services to use PostgreSQL-compatible queries

Documentation:
- Add comprehensive Docker deployment guide
- Add production deployment documentation
- Add infrastructure architecture documentation
- Update database setup guide for PostgreSQL-only
- Expand troubleshooting guide

Architecture & Validation:
- Add migration.yaml rules for SQL compatibility checking
- Enhance validate_architecture.py with migration validation
- Update architecture rules to validate Alembic migrations

Development:
- Fix duplicate install-all target in Makefile
- Add Celery/Redis validation to install.py script
- Add docker-compose.test.yml for CI testing
- Add squash_migrations.py utility script
- Update tests for PostgreSQL compatibility
- Improve test fixtures in conftest.py

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

app/services/product_service.py

@@ -278,9 +278,9 @@ class ProductService:
             # Prepare search pattern for LIKE queries
             search_pattern = f"%{query}%"
 
-            # Build base query with translation join
-            base_query = (
-                db.query(Product)
+            # Use subquery to get distinct IDs (PostgreSQL can't compare JSON for DISTINCT)
+            id_subquery = (
+                db.query(Product.id)
                 .outerjoin(
                     ProductTranslation,
                     (Product.id == ProductTranslation.product_id)
@@ -303,6 +303,11 @@ class ProductService:
                     )
                 )
                 .distinct()
+                .subquery()
+            )
+
+            base_query = db.query(Product).filter(
+                Product.id.in_(db.query(id_subquery.c.id))
             )
 
             # Get total count