kicad-validity B3+C+S: revert toast, corpus lint, .kicad_mod tier

B3 (editor): kicad-binding observes kdoc_meta.revertNonce (deduped, like
seedNonce) → DOC_REVERTED_EVENT → WasmTool doc-reverted-toast (15 s,
data-testid for the deferred e2e check).
C: tests/tools/corpus-lint.ts (npm run corpus:lint) — kicad_tools --lint
over the fixture corpora raw + shared-codec round-trips
(docToFile(fileToDoc(x))); the E3/wrapInBoardEnvelope-class gate. Skips
when output/kicad_tools.js isn't built; CI step lands when kicad_tools
joins the CI app set. 7 fixtures / 7 round-trips green.
S: --lint + --resave gain the .kicad_mod tier (pcbToolsLintFootprint /
pcbToolsResaveFootprint; writer needs CTL_FOR_LIBRARY or the board flags
strip the (version) header). Verified: qa footprint round-trip lints
clean, resave stamps 20260206, garbage exits 1. Also bumps pcbjam-shared
(mergeYUpdates for the bisect pass).

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01HLua64PCVwkQ1hpWdaf1Gm

wasm/cli/kicad_tools_main.cpp

@@ -14,9 +14,9 @@
  *   eeschema side (sym_convert_main.cpp) — everything else:
  *     kicad_tools --convert-lib <input.lib> <output.kicad_sym>
  *     kicad_tools --lint [--strict] <file> [<file>...]
- *                       (.kicad_pcb files get a FULL parse here — the pcbnew
- *                       parser is linked; the lint driver calls back into
- *                       pcbToolsLintBoard on the pcb side)
+ *                       (.kicad_pcb/.kicad_mod get a FULL parse here — the
+ *                       pcbnew parser is linked; the lint driver calls back
+ *                       into pcbToolsLintBoard/pcbToolsLintFootprint)
  *     kicad_tools --resave <file> <outdir>
  *                       (full parse + rewrite in the current file-format
  *                       version — kicad-validity 0001; .kicad_pcb via the