feat: incident correlation overhaul, signal-based auto-resolve, token fixes

Correlator
- Raise fast-path idle gate 30 → 90 min (tg_fast_path_idle_minutes)
- Fix disambiguate always-commits bug: run _call_fits_incident on winner
  before committing; fall through to new-incident creation if it fails
- Add unit-continuity path (path 1.5): matches all_active by shared unit
  IDs with a reassignment guard, bridges calls past the idle gate
- Add tag-based incident_type inference (_TAG_TYPE_HINTS) as GPT fallback,
  rescuing tagged calls that would have been dropped (616 observed orphans)
- Add master/child incident model: _create_master_incident, _demote_to_child,
  _add_child_to_master; new incidents stamped incident_type="master"
- Add cross-system parent detection (_find_cross_system_parent): two-signal
  scoring (road overlap=0.4, embedding≥0.78=0.3, proximity=0.3, threshold=0.5)
  wired into create-if-new path; creates master shell on first cross-system match
- Add maybe_resolve_parent: auto-resolves master when all children close;
  called from upload pipeline (LLM closure) and summarizer stale sweep
- Add signal-based auto-resolve via units_active/units_cleared tracking:
  GPT now extracts cleared_units per scene; _update_incident moves units
  between active/cleared lists and resolves the incident when active empties;
  stored on call doc for re-correlation sweep reuse
- Add _create_incident initialization of units_active/units_cleared fields

Re-correlation sweep
- Add corr_sweep_count + MAX_SWEEP_ATTEMPTS=3: orphans get 3 attempts
  then are tombstoned as corr_path="unlinked", ending the re-sweep loop
  (previously hammering each orphan 29-31 times per shift)

Intelligence extraction
- Add cleared_units to GPT prompt schema and rules
- Extract and propagate cleared_units per scene; merge across scenes;
  store on call doc for re-correlation sweep

Token management
- Fix token release bug: remove release_token call on discord_connected=False
  in MQTT checkin (transient Discord drops were orphaning bots mid-shift)
- Add PUT /tokens/{id}/prefer/{system_id} endpoint: lock a bot token to a
  system; pass _none as system_id to clear; stored bidirectionally on both
  token and system documents
- discord_join handler resolves preferred_token_id from system doc and passes
  system_name in MQTT payload

drb-c2-core/app/routers/upload.py

@@ -125,11 +125,13 @@ async def _run_extraction_pipeline(
             location_coords=scene["location_coords"],
             units=corr_units,
             vehicles=scene.get("vehicles"),
+            cleared_units=scene.get("cleared_units"),
         )
         if incident_id and incident_id not in incident_ids:
             incident_ids.append(incident_id)
         if scene["resolved"] and incident_id:
             await fstore.doc_set("incidents", incident_id, {"status": "resolved"})
+            await incident_correlator.maybe_resolve_parent(incident_id)
             logger.info(f"Auto-resolved incident {incident_id} (LLM closure detection)")
 
     if incident_ids:
@@ -224,11 +226,13 @@ async def _run_intelligence_pipeline(
                 location_coords=scene["location_coords"],
                 units=corr_units,
                 vehicles=scene.get("vehicles"),
+                cleared_units=scene.get("cleared_units"),
             )
             if incident_id and incident_id not in incident_ids:
                 incident_ids.append(incident_id)
             if scene["resolved"] and incident_id:
                 await fstore.doc_set("incidents", incident_id, {"status": "resolved"})
+                await incident_correlator.maybe_resolve_parent(incident_id)
                 logger.info(f"Auto-resolved incident {incident_id} (LLM closure detection)")
 
         # Correlator also runs for calls with no scenes (unclassified) to attempt