- Fix errcheck for db.Close() in testhelper.go
- Fix errcheck, nlreturn, wsl, gofumpt issues in genevents/main.go
- Fix gofumpt and wsl issues in library.go
The search_index is a contentless FTS5 table (content=''), which
SQLite does not support DELETE on. ClearSearchIndex now drops and
recreates the virtual table. Single-row DeleteSearchIndex becomes
a no-op since contentless FTS5 also cannot delete individual rows;
stale entries are harmless (search JOINs filter them out) and the
index is fully rebuilt during FullRescan.