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/cron_runner.py

@@ -26,7 +26,7 @@ import logging
 from datetime import datetime, timezone
 from pathlib import Path
 
-from config import settings
+from persona import persona_path as _persona_path
 
 logger = logging.getLogger(__name__)
 
@@ -45,12 +45,12 @@ _DOW = {
 # Storage
 # ---------------------------------------------------------------------------
 
-def crons_path() -> Path:
-    return settings.inara_path() / "CRONS.json"
+def crons_path(persona: str | None = None) -> Path:
+    return _persona_path(persona) / "CRONS.json"
 
 
-def load_crons() -> list[dict]:
-    p = crons_path()
+def load_crons(persona: str | None = None) -> list[dict]:
+    p = crons_path(persona)
     if not p.exists():
         return []
     try:
@@ -60,9 +60,9 @@ def load_crons() -> list[dict]:
         return []
 
 
-def save_crons(crons: list[dict]) -> None:
+def save_crons(crons: list[dict], persona: str | None = None) -> None:
     import json
-    crons_path().write_text(json.dumps(crons, indent=2) + "\n")
+    crons_path(persona).write_text(json.dumps(crons, indent=2) + "\n")
 
 
 # ---------------------------------------------------------------------------
@@ -134,16 +134,16 @@ async def run_job(job: dict) -> None:
     label = job.get("label", job.get("id", "cron"))
     section = f"\n## {label} — {_now_label()}\n\n{payload}\n"
 
-    inara_dir = settings.inara_path()
+    p_root = _persona_path(job.get("persona"))
 
     if job_type == "remind":
-        p = inara_dir / "REMINDERS.md"
+        p = p_root / "REMINDERS.md"
         existing = p.read_text() if p.exists() else ""
         p.write_text(existing.rstrip() + "\n" + section)
         logger.info("cron [remind] fired: %s", label)
 
     elif job_type == "note":
-        p = inara_dir / "SCRATCH.md"
+        p = p_root / "SCRATCH.md"
         existing = p.read_text() if p.exists() else ""
         p.write_text(existing.rstrip() + "\n" + section)
         logger.info("cron [note] fired: %s", label)
@@ -152,10 +152,11 @@ async def run_job(job: dict) -> None:
         logger.warning("cron: unknown type %r (job %s)", job_type, job.get("id"))
         return
 
-    # Record last_run
-    crons = load_crons()
+    # Record last_run in the right persona's CRONS.json
+    persona = job.get("persona")
+    crons = load_crons(persona)
     for c in crons:
         if c["id"] == job["id"]:
             c["last_run"] = datetime.now(timezone.utc).isoformat()
             break
-    save_crons(crons)
+    save_crons(crons, persona)