feat(cli): add layout audit command

[miguel-heygen]

Summary

Adds a new hyperframes layout command that loads a composition in headless Chrome, samples the timeline, and reports rendered layout issues such as text escaping bubbles/containers, clipped text, canvas overflow, and clipping-container escapes.

The command is designed for agent workflows: it supports JSON output with timestamps, selectors, bounding boxes, overflow sides, and fix hints. The HyperFrames CLI docs and shipped skills now tell agents to run it after lint and validate for user-visible compositions.

Validation

• bun run --filter @hyperframes/cli test
• bun run --filter @hyperframes/cli typecheck
• bunx oxlint packages/cli/src/commands/layout.ts packages/cli/src/utils/layoutAudit.ts packages/cli/src/utils/layoutAudit.test.ts packages/cli/src/cli.ts packages/cli/src/help.ts packages/cli/scripts/build-copy.mjs packages/cli/src/commands/layout-audit.browser.js
• bunx oxfmt --check packages/cli/src/commands/layout.ts packages/cli/src/utils/layoutAudit.ts packages/cli/src/utils/layoutAudit.test.ts packages/cli/src/cli.ts packages/cli/src/help.ts packages/cli/scripts/build-copy.mjs packages/cli/src/commands/layout-audit.browser.js docs/packages/cli.mdx skills/hyperframes-cli/SKILL.md skills/hyperframes/SKILL.md
• bun run --filter @hyperframes/studio build
• bun run --filter @hyperframes/cli build
• Built CLI fixture check: overflowing bubble reports text_box_overflow with right: 164.17px; corrected fixture returns ok: true.
• Agent-browser proof captured /tmp/hf-layout-proof-2026-04-24/layout-overflow.png and /tmp/hf-layout-proof-2026-04-24/layout-overflow.webm.