behavior change: Settings > Cache now has a 'Clear Tag Category
Cache' action that wipes the per-site tag_types table via the
existing db.clear_tag_cache() hook. This also drops the
__batch_api_probe__ sentinel so Gelbooru/Moebooru sites re-probe
the batch tag API on next use and repopulate the cache from a
fresh response.
Use case: category types like Character/Copyright/Meta appear
missing when the local tag cache was populated by an older build
that didn't map all of Gelbooru's type codes. Clearing lets the
current _GELBOORU_TYPE_MAP re-label tags cleanly instead of
inheriting whatever the old rows said.
behavior change: save_post_file's category_fetcher argument is now
keyword-only with no default, so every call site has to pass something
explicit (fetcher instance or None). Previously the =None default let
bookmark→library save and bookmark Save As slip through without a
fetcher at all, silently rendering %artist%/%character% tokens as
empty strings and producing filenames like '_12345.jpg' instead of
'greatartist_12345.jpg'.
BookmarksView now takes a category_fetcher_factory callable in its
constructor (wired to BooruApp._get_category_fetcher), called at save
time so it picks up the fetcher for whatever site is currently active.
tests/core/test_library_save.py pins the signature shape and the
three relevant paths: fetcher populates empty categories, None
accepted when categories are pre-populated (Danbooru/e621 inline),
fetcher skipped when template has no category tokens.
behavior change: a single mid-call network drop could previously
poison _batch_api_works=False for the whole site, forcing every
future ensure_categories onto the slower HTML scrape path. _do_ensure
now routes the unprobed case through _probe_batch_api, which only
flips the flag on a clean HTTP 200 with zero matching names; timeout
and non-200 responses leave the flag None so the next call retries
the probe.
The bug surfaced because fetch_via_tag_api swallows per-chunk
failures with 'except Exception: continue', so the previous code
path couldn't distinguish 'API returned zero matches' from 'the
network dropped halfway through.' _probe_batch_api already made
that distinction for prefetch_batch; _do_ensure now reuses it.
Tests in tests/core/api/test_category_fetcher.py pin the three
routes (transient raise, clean-200-zero-matches, non-200).
Both fetch_via_tag_api and _probe_batch_api built the same params
dict (with identical lstrip/startswith credential quirks) inline.
Pulled into _build_tag_api_params so future credential-format tweaks
have one site, not two.
