feat: per-role inject_mode, OTR fixes, hover metadata, send/stop tooltip

- inject_mode: per-role toggle (parallel to inject_datetime) gates the
  "Current mode: Off The Record" line in the system prompt; wired through
  model_registry, context_loader, chat router, orchestrator router, and
  local_llm settings UI

- OTR orchestrator fix: OrchestrateRequest now carries off_record;
  _finalize_job stores it per message and gates log_turn on it; JS
  orchestrate payload sends off_record correctly

- Per-message hover metadata: removed always-visible .model-tag; replaced
  with .msg-meta strip in the action bar (hover-only); shows model label,
  host, fallback indicator, and OTR badge; stored in session JSON

- Send/stop button tooltip: shows role + model and (when tools on)
  separate orchestrator model + engine label; live elapsed timer on stop
  button via startRunTimer/stopRunTimer

- OrchestratorResult.backend_label: new field; openai_orchestrator fills
  it; finalize_job propagates it to job dict and session messages

- GET /backend: exposes orchestrator_model label so the frontend tooltip
  can show both models separately

- TODO: session delete confirmation added

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

cortex/routers/orchestrator.py

@@ -12,6 +12,7 @@ Designed to be triggered from:
 
 import asyncio
 import logging
+import platform
 import uuid
 from datetime import datetime, timezone
 
@@ -57,6 +58,7 @@ class OrchestrateRequest(BaseModel):
     user: str = "scott"
     persona: str = "inara"
     chat_role: str = "chat"             # role used for the final response (decoupled from tool-loop model)
+    off_record: bool = False            # skip session log; inject OTR mode line into system prompt
 
 
 class OrchestrateResponse(BaseModel):
@@ -74,6 +76,8 @@ class JobStatusResponse(BaseModel):
     response: str | None = None
     tool_calls: list[dict] | None = None
     backend: str | None = None
+    backend_label: str | None = None
+    host: str | None = None
     gemini_summary: str | None = None
     error: str | None = None
     pending_confirmation: dict | None = None  # {tools: [{name, args}], message: str}
@@ -109,6 +113,7 @@ async def orchestrate(req: OrchestrateRequest) -> OrchestrateResponse:
         "error": None,
         "pending_confirmation": None,
         "_user": user,
+        "_off_record": req.off_record,
     }
 
     async with _jobs_lock:
@@ -204,6 +209,8 @@ async def _run_job(job_id: str, req: OrchestrateRequest, user: str) -> None:
             include_short=req.include_short,
             role_append=role_cfg.get("system_append", ""),
             inject_datetime=role_cfg.get("inject_datetime", True),
+            inject_mode=role_cfg.get("inject_mode", True),
+            mode="otr" if req.off_record else "chat",
         )
 
         session_id = req.session_id or generate_session_id()
@@ -270,7 +277,7 @@ async def _run_job(job_id: str, req: OrchestrateRequest, user: str) -> None:
                         job_id, len(result.checkpoint.pending_tools))
             return
 
-        await _finalize_job(job_id, result, session_id, req.task, history)
+        await _finalize_job(job_id, result, session_id, req.task, history, off_record=req.off_record)
 
     except Exception as e:
         logger.exception("Orchestrator job failed: %s", job_id)
@@ -316,12 +323,13 @@ async def _resume_job(
             return
 
         async with _jobs_lock:
-            session_id = _jobs[job_id].get("session_id") or ""
-            task = _jobs[job_id].get("task", "")
+            session_id  = _jobs[job_id].get("session_id") or ""
+            task        = _jobs[job_id].get("task", "")
+            off_record  = _jobs[job_id].get("_off_record", False)
 
         from session_store import load as load_session
         history = load_session(session_id) if session_id else []
-        await _finalize_job(job_id, result, session_id, task, history)
+        await _finalize_job(job_id, result, session_id, task, history, off_record=off_record)
 
     except Exception as e:
         logger.exception("Orchestrator resume failed: %s", job_id)
@@ -340,6 +348,7 @@ async def _finalize_job(
     session_id: str,
     task: str,
     history: list,
+    off_record: bool = False,
 ) -> None:
     """Save session, log the turn, and mark the job complete."""
     from session_store import save as save_session, generate_session_id
@@ -348,10 +357,19 @@ async def _finalize_job(
     if not session_id:
         session_id = generate_session_id()
 
-    history.append({"role": "user", "content": task})
-    history.append({"role": "assistant", "content": result.response})
+    host = platform.node()
+    history.append({"role": "user", "content": task, "off_record": off_record})
+    history.append({
+        "role": "assistant",
+        "content": result.response,
+        "backend": result.backend,
+        "backend_label": result.backend_label,
+        "host": host,
+        "off_record": off_record,
+    })
     save_session(session_id, history)
-    log_turn(session_id, task, result.response)
+    if not off_record:
+        log_turn(session_id, task, result.response)
 
     now = datetime.now(timezone.utc).isoformat()
     async with _jobs_lock:
@@ -362,6 +380,8 @@ async def _finalize_job(
             "response": result.response,
             "tool_calls": result.tool_calls,
             "backend": result.backend,
+            "backend_label": result.backend_label,
+            "host": host,
             "gemini_summary": result.gemini_summary,
         })
     logger.info("Orchestrator job complete: %s (%d tool calls)", job_id, len(result.tool_calls))