chore(sync): cascade ignore-block + repo lint cleanup

Cascade adds fleet-canonical-begin/end block to .config/oxlintrc.json
and .config/oxfmtrc.json so downstream skips wheelhouse-owned files.
Also resolves 163 pre-existing lint errors blocking commits:

- prefer-exists-sync (5): annotate fs.stat callsites that need stats
  metadata (mtime, size, isDirectory).
- no-dynamic-import-outside-bundle (9): annotate lazy-import callsites
  in scripts and tests with concrete reasons.
- no-fetch-prefer-http-request (3): file-level disable on docs-site
  comments.js + sw.js (browser/service-worker, no Node http-request
  lib available).
- no-placeholders (3): strip a real TODO in comments.js; annotate
  scripts that document the markers they detect.
- sort-source-methods (143): file-level disable in 8 files where
  helpers are deliberately grouped by domain/pipeline phase (parser
  ecosystem affinity in url-converter.ts, predicate/mutator/transform
  groups in strings.ts, etc.) — alphabetical scatter would harm
  reader comprehension.

Also fixes scripts/test.mts pre-commit invocation to point at
.config/oxlintrc.json (stale root-relative path after the .config/
move).

Author: jdalton