#4291 feat(screenshot): burst capture with --count and --interval-ms

Summary

Recording an animation today means repeating single screenshots by hand — six separate re-implementations showed up in the audited sessions. screenshot --count N --interval-ms T (count ≥ 2, interval ≥ 100 ms) captures a frame series in one request and returns per-frame frames entries (path, capturedAtMs, displayRotation) alongside the first frame's usual fields, so motion evidence is one call with timestamps instead of a hand-built loop.

10 files changed (contracts flag keys and validation, daemon capture loop, CLI output, tests).

Validation

• Head: 6764cfb8e on a68693c72 (includes review-fix commit: frame entries survive the client boundary whitelist with per-frame validation).
• pnpm run typecheck, pnpm run lint, screenshot and contracts tests, integration-progress --check, fallow, freerange: pass locally.
• Independent cold review: 1 blocker fixed (frame passthrough), rest applied. CI runs the full gates on push.

🤖 Generated with Claude Code

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