feat(auth): implement site-based passcode-to-JWT endpoint

- Add POST /api/authenticate_passcode to verify site access codes
- Refactor sign_jwt to support arbitrary role flags (super, admin, etc.)
- Update dependencies_v3 to extract role flags from JWT payloads
- Add E2E test for passcode auth verification

app/routers/dependencies_v3.py

@@ -89,13 +89,22 @@ def get_account_context_optional(
             resolved_account_id_random = '--- NO ACCOUNT ---'
             auth_method = 'bypass'
 
+    is_admin = (auth_method == 'bypass')
+    is_manager = (auth_method == 'bypass')
+    is_super = (auth_method == 'bypass')
+
+    if resolved_token_payload:
+        if resolved_token_payload.get('administrator'): is_admin = True
+        if resolved_token_payload.get('manager'): is_manager = True
+        if resolved_token_payload.get('super'): is_super = True
+
     return AccountContext(
         account_id=resolved_account_id,
         account_id_random=resolved_account_id_random,
         auth_method=auth_method,
-        administrator=(auth_method == 'bypass'),
-        manager=(auth_method == 'bypass'),
-        super=(auth_method == 'bypass'),
+        administrator=is_admin,
+        manager=is_manager,
+        super=is_super,
         token_payload=resolved_token_payload
     )