chore(vocero): remove the legacy ApiPilot integration (#3)

Vocero now retrieves AquaPortal content through authenticated MCP. This removes the obsolete ApiPilot integration from the API and browser while preserving the separately deployed speech pipeline.

Release notes:

- Removed ApiPilot endpoints, configuration, credential overrides, and HTTP/realtime tool execution.
- Removed browser ApiPilot catalog loading and prompt generation while retaining authenticated MCP discovery.
- Updated regression coverage and operating documentation for the retired routes and settings.

Reviewed-on: AquaPortal/s2s#3

vocero-api/vocero_api/api/router.py

@@ -2,7 +2,7 @@
 
 from fastapi import APIRouter
 
-from vocero_api.api.routes import apipilot, caller, config, conversations, search, sessions
+from vocero_api.api.routes import caller, config, conversations, search, sessions
 from vocero_api.models.responses import ReasoningResponse
 from vocero_api.realtime.proxy import realtime_proxy
 from vocero_api.services.reasoning import reasoning
@@ -10,7 +10,6 @@ from vocero_api.services.reasoning import reasoning
 router = APIRouter()
 router.include_router(config.router)
 router.include_router(conversations.router)
-router.include_router(apipilot.router)
 router.add_api_route("/api/reasoning", reasoning, methods=["POST"], response_model=ReasoningResponse)
 router.add_api_websocket_route("/v1/realtime", realtime_proxy)
 router.include_router(caller.router)