fix(dates): year-gate the filename wall-clock patterns (#160)

match_filename_date only gated the unix-timestamp branch to years
1995..=now+1; the five wall patterns returned any NaiveDateTime. Counters
and IDs shaped like YYYYMMDD_HHMMSS (an app's VID_<counter>_<HHMMSS>,
Facebook's <8 digits>_<id>_o.jpg) became dates of record in years from
267 to 9985: 67 rows on prod, all via screenshot_compact.

Both branches now share plausible_filename_year; a wall miss falls
through to the next pattern and then the rest of the waterfall. The
filename audit no longer proposes these dates.

A data migration clears the five date columns on filename-sourced rows
dated outside [1995, 2028) UTC, so backfill_missing_date_taken
re-resolves them from EXIF / exiftool / fs time on the next ticks.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

migrations/2026-10-16-000000_reresolve_implausible_filename_dates/down.sql

@@ -0,0 +1,3 @@
+-- Data fix only: the cleared dates were wrong and are re-resolved by the
+-- drain, so there is nothing to restore.
+SELECT 1;