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>

scripts/install.py

@@ -355,6 +355,52 @@ def validate_configuration(env_vars: dict) -> dict:
             "items": ["Set PLATFORM_DOMAIN for your deployment"]
         }
 
+    # -------------------------------------------------------------------------
+    # Celery / Redis Task Queue
+    # -------------------------------------------------------------------------
+    redis_url = env_vars.get("REDIS_URL", "")
+    use_celery = env_vars.get("USE_CELERY", "false").lower() == "true"
+    flower_url = env_vars.get("FLOWER_URL", "")
+    flower_password = env_vars.get("FLOWER_PASSWORD", "")
+
+    if use_celery:
+        if redis_url:
+            celery_items = [f"Redis: {redis_url.split('@')[-1] if '@' in redis_url else redis_url}"]
+
+            if flower_url:
+                celery_items.append(f"Flower: {flower_url}")
+            else:
+                celery_items.append("FLOWER_URL not set (monitoring disabled)")
+
+            if flower_password and flower_password != "changeme":
+                celery_items.append("Flower password configured")
+            elif flower_password == "changeme":
+                celery_items.append("WARNING: Change FLOWER_PASSWORD for production!")
+
+            results["celery"] = {
+                "status": "ok",
+                "message": "Celery enabled with Redis",
+                "items": celery_items
+            }
+        else:
+            results["celery"] = {
+                "status": "missing",
+                "message": "Celery enabled but Redis not configured",
+                "items": [
+                    "Set REDIS_URL (e.g., redis://localhost:6379/0)",
+                    "Or disable Celery: USE_CELERY=false"
+                ]
+            }
+    else:
+        results["celery"] = {
+            "status": "warning",
+            "message": "Celery disabled (using FastAPI BackgroundTasks)",
+            "items": [
+                "Set USE_CELERY=true for production",
+                "Requires Redis: docker-compose up -d redis"
+            ]
+        }
+
     return results