feat(video): narrated presentation videos (WM-001) - #2

Closes nothing yet; tracks #1 (WM-001).

What this adds

• Three skills: tutorial-video-scripting (purpose), presentation-video-production and presentation-video-review (form). The naming seam leaves room for other purposes in the same form later.
• Shared guides: shared/media/spoken-style.md, shared/media/speech-synthesis.md.
• Project template templates/presentation-video/: Remotion composition that reads one timeline.json, plus tools for the script check, per-line voicing with a content-addressed cache, the timeline, pace/loudness/pause measurement, setting probes, read-back verification, take splitting, stills and rendering; playbook PB-WM-VIDEO-001.
• Credentials: env/*.env.example without values. Real env files, a project's video-profile.json and pronunciation.json are ignored by Git; only the *.example.json files are tracked. ElevenLabs is used through the connector, without an API key.
• Routing: method.json (version 0.2.0), handoff and selection policies, trigger matrix and evaluation cases.
• Spec artifacts: docs/specs/WM-001-presentation-video/ (spec, plan, research, tasks, rehearsal).

Decisions worth a look

• The timeline owns every pause. Silence inside each sound file is measured and subtracted; the audible pause was 1.0–1.2 s against a configured 0.6 s, and is now 0.65 s by default (0.66 s measured in the rendered sample).
• Provider settings are probed before they are relied on: with the voice family tested, a small rate change had no measurable effect and pause markup was ignored.
• Voices must cover the target language and English; the credential check now matches the voice name exactly and reports languages the profile claims but the provider does not list.
• No length recommendation for tutorials; above 45 minutes the script check proposes a split.

Core sync

The second commit syncs Method Core at 426e035 (phense/method-core#1): the issue label now comes from the bundling method's method.json instead of a fixed engineering-method. The lock pins that branch commit — merge phense/method-core#1 with a merge commit (not squash) before or together with this PR, otherwise the pinned revision is orphaned and a re-sync is needed. Issue #1 is relabelled to writing-method.

Verification

• python3 -m unittest discover -s tests -t . — OK (241 tests)
• python3 scripts/validate-plugin — exit 0
• python3 scripts/sync-core --check — passed, revision 426e035, 69 files
• Rehearsal on the sample video (Azure voicing, timeline, stills, local and remote render, measurements passed, one ElevenLabs generation): docs/specs/WM-001-presentation-video/rehearsal.md. The render was not repeated after the review fixes.

Still open

• T032b: playbook-review of the playbook template at this revision
• T033: convergence, FEATURES.md entry
• Live trigger evaluations on the hosts

🤖 Generated with Claude Code