feat: multi-persona support (single Cortex, multiple users)

- Add cortex/persona.py: ContextVar-based per-request routing with
  path traversal protection and persona validation
- Migrate inara/ → personas/inara/ (git history preserved via git mv)
- config.py: add personas_root(), inara_path() delegates to personas/inara
- All 14 settings.inara_path() call sites replaced with persona_path()
- ChatRequest + OrchestrateRequest: add persona field (default: "inara")
  with validation at request entry before any processing
- memory_distiller: add optional persona param for future per-persona distill
- cron_runner/tools/cron: stamp persona on jobs, prefix APScheduler IDs
  (persona:job_id) to prevent collisions across personas
- scheduler: _load_user_crons() iterates all personas at startup

Adding a new persona: create personas/<name>/ with IDENTITY.md + SOUL.md.
Auth: handled at nginx level (inject X-Cortex-Persona header per subdomain).
Future: persona maps to Aether account_id_random for full integration.

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

cortex/scheduler.py

@@ -84,34 +84,38 @@ def start() -> None:
 
 
 def _load_user_crons() -> None:
-    """Register all enabled user-defined cron jobs from CRONS.json."""
+    """Register all enabled user-defined cron jobs across all personas."""
     import asyncio
     try:
         from cron_runner import load_crons, parse_schedule, run_job
+        from persona import list_personas
     except ImportError as e:
-        logger.warning("could not import cron_runner: %s", e)
+        logger.warning("could not import cron modules: %s", e)
         return
 
-    crons = load_crons()
-    loaded = 0
-    for job in crons:
-        if not job.get("enabled", True):
-            continue
-        try:
-            kwargs = parse_schedule(job["schedule"])
-            _scheduler.add_job(
-                lambda j=job: asyncio.ensure_future(run_job(j)),
-                "cron",
-                id=job["id"],
-                replace_existing=True,
-                **kwargs,
-            )
-            loaded += 1
-        except Exception as e:
-            logger.warning("cron job %s skipped: %s", job.get("id"), e)
+    total = 0
+    for persona_name in list_personas():
+        for job in load_crons(persona_name):
+            if not job.get("enabled", True):
+                continue
+            # Ensure persona is stamped on the job for run_job() to resolve paths
+            job.setdefault("persona", persona_name)
+            try:
+                kwargs = parse_schedule(job["schedule"])
+                sched_id = f"{persona_name}:{job['id']}"
+                _scheduler.add_job(
+                    lambda j=job: asyncio.ensure_future(run_job(j)),
+                    "cron",
+                    id=sched_id,
+                    replace_existing=True,
+                    **kwargs,
+                )
+                total += 1
+            except Exception as e:
+                logger.warning("cron %s/%s skipped: %s", persona_name, job.get("id"), e)
 
-    if loaded:
-        logger.info("loaded %d user cron job(s)", loaded)
+    if total:
+        logger.info("loaded %d user cron job(s) across %d persona(s)", total, len(list_personas()))
 
 
 def stop() -> None: