findings R: coverage for the demo-ledger fixes (R-2, R-3, R-4, R-9) — tests only

- R-9: tests/kicad/project-sync.spec.ts gains an effect-asserting test —
  stages a self-contained footprint lib (ecc83 R_Axial as SyncFixture.pretty
  + absolute-uri fp-lib-table via a new stageAndOpen beforeOpen hook), presses
  Update PCB, and asserts the board's footprint references through
  kicadCollabSnapshot/kicadCollabTestItemBlob (R777, then R888 after a
  schematic rewrite + re-sync). Red-first: the dialog report said "Add R777"
  while the board stayed empty when the button click never landed.
- R-2: tests/kicad/via-snapshot-assert.spec.ts — two-via board, exact widths
  + no PCB_VIA::GetWidth wx assert line in the console.
- R-4: tests/web/console-copy.spec.ts — Ctrl/Cmd+C over a console selection
  fires `copy` (guard stops the keydown before wx); canvas pointerdown
  collapses the selection. ControlOrMeta: headless engines use the HOST copy
  accelerator regardless of the device UA.
- R-3: workers/cdn gets a vitest harness (package.json + lockfile) and
  test/index.test.ts with a workerd-like stub bucket (always-defined range):
  plain GET is 200/no Content-Range, Range → 206, HEAD/304/404/405/OPTIONS.
  Mutation-verified (pre-1ea35f7 gating → 2 reds). CI step added after the
  corpus lint; node_modules gitignored.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_015j8uFzSjwRrAeJ85QWVLQa

workers/cdn/package.json

@@ -0,0 +1,12 @@
+{
+  "name": "pcbjam-cdn-worker",
+  "private": true,
+  "type": "module",
+  "description": "Static CDN worker (R2-backed) — unit tests only; deployed via wrangler from CI.",
+  "scripts": {
+    "test": "vitest run"
+  },
+  "devDependencies": {
+    "vitest": "^3.0.0"
+  }
+}