feat: increase default max iterations and add seed-finding fix pipeline to maintenance agents

- Bump DEFAULT_MAX_ITER from 40 to 60 in agents/base.py for longer agent runs
- Add seed_findings parameter to MaintenanceAgent.task_prompt() enabling targeted fix mode from prior check results
- Extend write_reports() with incomplete flag to track partial completion
- Introduce _LAST_CHECK cache in maestro.py to store check findings for subsequent fix runs
- Modify _dispatch() to pass seed findings to fix mode and include seeded_from_check in response
- Add incomplete field to orchestrator.py fleet results for consistency across agent outputs

agents/core/__init__.py

@@ -155,6 +155,7 @@ def write_reports(
     started: datetime,
     finished: datetime,
     cost: Optional[dict[str, Any]] = None,
+    incomplete: bool = False,
 ) -> dict[str, Any]:
     REPORTS_DIR.mkdir(parents=True, exist_ok=True)
     items = findings()
@@ -166,6 +167,7 @@ def write_reports(
         "mode": mode,
         "started_at": started.isoformat(),
         "finished_at": finished.isoformat(),
+        "incomplete": incomplete,
         "summary": summary,
         "cost": cost or {},
         "findings": items,