fix: wrap non-finished batch jobs to fail fast on download

When poll times out with 2/3 jobs finished, calling
download_results() on a still-running job blocks for 30 min
(HTTP read timeout). Now non-finished jobs are wrapped with
_SkippedJob that raises immediately — the harvest methods'
existing try/except handles this as graceful degradation.

Generated with [Claude Code](https://claude.ai/code)
via [Happy](https://happy.engineering)

Co-Authored-By: Claude <noreply@anthropic.com>
Co-Authored-By: Happy <yesreply@happy.engineering>

app/worker.py

@@ -22,6 +22,16 @@ BATCH_POLL_INTERVAL = 30  # seconds between status checks
 BATCH_TIMEOUT = 5400  # 90 minutes per indicator
 
 
+class _SkippedJob:
+    """Stub for batch jobs that didn't finish — fails fast on download."""
+    def __init__(self, job_id: str):
+        self.job_id = job_id
+    def download_results(self, *a, **kw):
+        raise RuntimeError(f"Job {self.job_id} not finished, skipping download")
+    def status(self):
+        return "skipped"
+
+
 def _save_spatial_json(spatial, status_value: str, path: str) -> None:
     """Serialize spatial data to JSON for the frontend."""
     if spatial is None:
@@ -113,13 +123,19 @@ async def process_job(job_id: str, db: Database, registry: IndicatorRegistry) ->
                 # Harvest if any job finished (harvest methods handle per-job failures)
                 any_finished = any(s == "finished" for s in statuses)
                 if any_finished:
+                    # Wrap non-finished jobs so download_results() fails fast
+                    # instead of blocking for 30 min on a still-running job
+                    harvest_jobs = [
+                        j if s == "finished" else _SkippedJob(getattr(j, 'job_id', '?'))
+                        for j, s in zip(jobs, statuses)
+                    ]
                     await db.update_job_progress(job_id, indicator_id, "downloading")
                     try:
                         result = await indicator.harvest(
                             job.request.aoi,
                             job.request.time_range,
                             season_months=job.request.season_months(),
-                            batch_jobs=jobs,
+                            batch_jobs=harvest_jobs,
                         )
                     except Exception as exc:
                         logger.warning("Harvest failed for %s, using fallback: %s", indicator_id, exc)