refactor(routers): comment out legacy endpoints across multiple routers

Disabled legacy routes that are superseded by V3 equivalents. Code is
commented out (not deleted) pending final verification and cleanup pass.

- registry.py: remove sql, lookup (/lu), websockets, websockets_redis;
  clean up dead imports (contact, event_person, etc.)
- data_store.py: comment out legacy CRUD and code-lookup endpoints;
  keep V3 code-lookup routes active; add TODO for action path rename
- api.py: comment out Api_Base CRUD, get_id (internal ID leak),
  and sql_test (debug) endpoints
- aether_cfg.py: comment out legacy Flask cfg endpoint
- user.py: comment out legacy user endpoints
- util_email.py: minor cleanup

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

app/routers/util_email.py

@@ -20,6 +20,8 @@ router = APIRouter()
 
 # ### BEGIN ### API Utility: Email ### util_email_send_obj() ###
 # Updated 2023-06-27
+# NOTE: This is actively in use 2026-03-24 -Scott
+# This is marked for deprecation and must be migrated to Aether API v3 standards!
 @router.post('/util/email/send', response_model=Resp_Body_Base)
 async def util_email_send_obj(
         email_send_obj: Email_Send_Base,