fix(skills,cli): close four reproduced contract gaps from the CLI feedback digest (#2476)

* fix(cli): invalidate the skills nudge cache after a successful install/update/check

The passive "N skills out of date or missing" nudge reads a 24h config
cache that only the background check (on non-skills commands) ever wrote.
The skills commands themselves are excluded from the nudge pipeline, so a
successful `skills update`/install/check never refreshed or dropped the
cached verdict — the pre-install count kept printing on every other
command for up to 24h.

Reconcile commands now drop the cached verdict (counts + timestamp) so
the next command's background check re-runs for real. The offline
presence-only path deliberately keeps the cache: that run learned nothing
about freshness.

* fix(skills): win32-safe npx spawns in media-use + accurate whisper wording

The Whisper transcribe fallback and the Kokoro local-TTS delegation both
spawned a bare "npx" via execFileSync — on Windows npx is npx.cmd, which
spawn cannot exec, so both paths died with `spawnSync npx ENOENT`. Route
them through the skill's existing resolveSpawnCommand (node + npx-cli.js
on win32, no shell:true), same as the audio engine's TTS spawns.

Also corrects the "bundled with the hyperframes CLI" claim about
whisper.cpp: it is resolved from PATH / installed via Homebrew / built
from source with git+cmake on first use, and models download from
HuggingFace — nothing whisper is shipped in the package.

* feat(skills): canonical fully-silent marker + auth status exit-code docs

product-launch's Step 3.1 gate said "or the project is marked silent"
but nothing defined how to mark one, and audio.mjs unconditionally
retrieved BGM. Define the canonical marker — `music: none` in the
storyboard's top YAML block, plus no SCRIPT.md — and honor it:
audio generate produces nothing (removing stale audio_meta.json, since
absence is what assemble treats as silent), and `music: none` with
narration keeps TTS while turning BGM off.

Also documents the `auth status` exit-code contract (exit 1 while
signed out is the normal offline state, not a failure) in the
product-launch Step 0 note and the CLI skill's cloud reference.

* fix(skills): transient-init retry for standalone animation-map and contrast-report

The standalone helpers called initializeSession exactly once, so a valid
modular project — whose sub-composition timelines register asynchronously
— could hit the readiness deadline and die with the transient
"zero duration / Runtime ready: false" diagnostic the render pipeline
retries (probeStage). Add initializeSessionWithRetry to the shared
package-loader (both byte-identical copies): close the crashed session
and retry once with a fresh browser, gated by the engine's canonical
isTransientBrowserError — now re-exported from @hyperframes/producer,
with a frozen fallback pattern list for older published packages. The
"Runtime ready: true" fast-fail (a genuine authoring bug) still fails
without a retry.

* feat(skills): extend the fully-silent marker to faceless-explainer and pr-to-video

Both workflows reuse product-launch's audio model — their Step 3.1 gates
carried the same undefined "marked silent" phrase, and their (intentionally
identical) audio.mjs copies had the same unconditional BGM retrieve. Port
the `music: none` marker handling into both copies, define the marker in
their SKILL.md Step 3.1 and story-design references, and turn the
copies' "intentionally identical" header claim into a byte-identity pin
test so the next fix can't silently miss one of them.

* test(cli): reset the prune mock explicitly instead of relying on restoreAllMocks

The converge test's toHaveBeenCalledTimes(1) held only because vitest 3's
vi.restoreAllMocks() clears vi.fn() call state; vitest 4 restores spies
only, so the count would accumulate across tests and fail. Reset
pruneOrphanedLockEntries in beforeEach like the other manifest mocks —
passes under both vitest 3.2.4 (pinned) and vitest 4.

* test(skills): close review findings — package-loader pin, whisper win32 parity, quoted-none

Review follow-ups on #2476:

- package-loader.mjs byte-identity pin (the elevated concern): the two
  copies now carry initializeSessionWithRetry + FALLBACK_TRANSIENT_PATTERNS,
  exactly the shared-logic shape a future fix could land in one copy and
  miss in the other — same enforcement as the audio.mjs pin.
- whisper win32 call-site parity: runWhisper's npx resolution lifted into
  lib/npx-sync.mjs (resolveNpxInvocation, injectable params matching the
  localTtsGenerate idiom) with the same three-branch coverage as the
  Kokoro site — plus the hard-fail contract (throws actionably, since the
  whisper fallback has no next provider to fall through to).
- quoted music: "none" pin: the vendored storyboard parser strips matching
  quotes at parse time (stripQuotes), so the silent marker already accepts
  the quoted spelling — pinned so that stays true.

skills/media-use/scripts/transcribe.mjs

@@ -15,6 +15,7 @@ import { basename, extname, join, resolve } from "node:path";
 import { parseArgs } from "node:util";
 import { mergeTokensToWords } from "./lib/parakeet-words.mjs";
 import { track } from "./lib/telemetry.mjs";
+import { resolveNpxInvocation } from "./lib/npx-sync.mjs";
 
 // The DEFAULT local transcription path. Prefers NVIDIA Parakeet-TDT via
 // parakeet-mlx, which beats whisper.cpp on the Open ASR Leaderboard (~6.05% vs
@@ -24,8 +25,9 @@ import { track } from "./lib/telemetry.mjs";
 // captions / the audio engine.
 //
 // Parakeet v3 covers English + 25 European languages. For other languages, or
-// when parakeet-mlx is not installed, it falls back to the packaged whisper.cpp
-// (`hyperframes transcribe`, 99 languages). `--engine` forces one.
+// when parakeet-mlx is not installed, it falls back to whisper.cpp via
+// `hyperframes transcribe` (99 languages; the CLI resolves/builds whisper.cpp
+// on first use — it is not bundled). `--engine` forces one.
 
 const { values: args } = parseArgs({
   options: {
@@ -120,14 +122,20 @@ function runParakeet(runner) {
   }
 }
 
-// whisper.cpp via the packaged CLI: writes transcript.json into --dir; relocate to --out.
+// whisper.cpp via the hyperframes CLI (fetched/built on first use — see
+// SKILL.md): writes transcript.json into --dir; relocate to --out.
 function runWhisper() {
   const workDir = mkdtempSync(join(tmpdir(), "media-use-whisper-"));
   try {
-    execFileSync("npx", ["hyperframes", "transcribe", inputPath, "--dir", workDir], {
-      stdio: ["ignore", "pipe", "pipe"],
-      timeout: 1_800_000,
-    });
+    // On Windows a bare "npx" is npx.cmd, which execFileSync cannot exec
+    // (spawnSync npx ENOENT) — resolveNpxInvocation reroutes it through
+    // node + npx-cli.js (and throws actionably when it can't), same
+    // mechanism as the audio engine's TTS spawns.
+    const resolved = resolveNpxInvocation(
+      ["hyperframes", "transcribe", inputPath, "--dir", workDir],
+      { stdio: ["ignore", "pipe", "pipe"], timeout: 1_800_000 },
+    );
+    execFileSync(resolved.cmd, resolved.args, resolved.opts);
     const produced = join(workDir, "transcript.json");
     if (!existsSync(produced)) throw new Error("whisper produced no transcript.json");
     const tmp = `${outPath}.tmp-${process.pid}`;