refactor: rename Wizamart to Orion across entire codebase

Replace all ~1,086 occurrences of Wizamart/wizamart/WIZAMART/WizaMart
with Orion/orion/ORION across 184 files. This includes database
identifiers, email addresses, domain references, R2 bucket names,
DNS prefixes, encryption salt, Celery app name, config defaults,
Docker configs, CI configs, documentation, seed data, and templates.

Renames homepage-wizamart.html template to homepage-orion.html.
Fixes duplicate file_pattern key in api.yaml architecture rule.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

docs/backend/store-in-token-architecture.md

@@ -55,7 +55,7 @@ def get_product(
 │       "sub": "user_id",                                         │
 │       "username": "john.doe",                                   │
 │       "store_id": 123,          ← Store context in token     │
-│       "store_code": "WIZAMART",  ← Store code in token       │
+│       "store_code": "ORION",  ← Store code in token       │
 │       "store_role": "Owner"      ← Store role in token       │
 │     }                                                            │
 └─────────────────────────────────────────────────────────────────┘
@@ -436,14 +436,14 @@ def test_store_in_token():
     token_data = auth_manager.create_access_token(
         user=user,
         store_id=123,
-        store_code="WIZAMART",
+        store_code="ORION",
         store_role="Owner",
     )
 
     # Verify token contains store data
     payload = jwt.decode(token_data["access_token"], secret_key)
     assert payload["store_id"] == 123
-    assert payload["store_code"] == "WIZAMART"
+    assert payload["store_code"] == "ORION"
     assert payload["store_role"] == "Owner"
 
 def test_api_endpoint_uses_token_store():
@@ -517,7 +517,7 @@ The architecture enforces a strict layered pattern for where exceptions should b
 ┌────────────────────────────────────────────────────────────────────────────┐
 │  GLOBAL EXCEPTION HANDLER - app/exceptions/handler.py                      │
 │                                                                            │
-│  ✅ Catches all WizamartException subclasses                               │
+│  ✅ Catches all OrionException subclasses                               │
 │  ✅ Converts to appropriate HTTP responses                                 │
 │  ✅ Provides consistent error formatting                                   │
 └────────────────────────────────────────────────────────────────────────────┘