generated_images was UNIQUE(prompt_id, filename) on the basename, so
ComfyUI's same-named files in different date folders were silently
ignored by INSERT OR IGNORE, and the lastrowid == 0 branch after it
never ran. The table now carries file_path (normcase/normpath/abspath
of the image path) with UNIQUE(prompt_id, file_path); the migration
collapses rows that normalise to one file and supersedes the old
basename migration, which would otherwise undo it on every start.
search_prompts and the tag search escaped nothing, so 100% matched
'100 percent' and a_b matched aXb; user text now goes through
escape_like with ESCAPE. save_prompt no longer stamps last_used_at, the
usage backfill runs only on the upgrade that adds the columns, and the
Recently Used / Most Used orders put never-run prompts (NULL) after run
ones instead of first.