Trigger Backfill Ttab

P0-SOTA: bulk TTABYR backfill in a DETACHED subprocess.

The class-relatedness matrix + AUC 0.6315 opposition model both read from ttab_proceedings/ttab_parties/ttab_properties. Those tables are populated ONLY by this bulk script — the daily cron (cron_ttab_v3_delta.py) writes to a different schema (ttab_decisions). So without this endpoint firing on a schedule, the moat data drifts monotonically.

Wall-clock: ~4-8h (6 zips × ~74MB each, streamed parse to sqlite). Detached subprocess so the HTTP call returns immediately.

Query params: max_files — cap chunks (1 = smoke; default all 6) download_only — pull zips, don't ingest ingest_only — use cached zips already on /data/uspto_bulk/