initial code (#2)

* feat: initial code port from hyperframes-internal

Port all OSS-ready packages from the internal monorepo:
- @hyperframes/core — shared types, HTML generation, GSAP utilities, runtime
- @hyperframes/cli — CLI for creating, previewing, and rendering compositions
- @hyperframes/engine — framework-agnostic rendering engine (BeginFrame + FFmpeg)
- @hyperframes/producer — video rendering pipeline (Puppeteer + FFmpeg)
- @hyperframes/ui-player — browser-based video player component
- @hyperframes/studio — composition editor (React frontend + Hono backend)

Includes regression test suite with Docker-based test harness.

All HeyGen-internal references, deployment infrastructure, and
proprietary assets have been removed. Package names migrated
from @app/* to @hyperframes/*.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* fix: scrub internal codenames and stale references from OSS port

- Replace static.heygen.ai runtime URLs in test fixtures
- Remove internal CDN publish script (publish-hyperframe-runtime.ts)
- Replace sandbox-studio, sandbox-interceptor, __magicEditRuntime
  with neutral names (studio, hyperframe-runtime, __hyperframeRuntime)
- Fix stale Vault API / localhost references in docs
- Remove broken deprecated_studio link

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* fix: remove remaining internal codenames and stale references

- Delete stale producer README.md and PIPELINE.md (referenced nonexistent files)
- Replace "Cerberus" codename with "HyperFrames" in test design reviews
- Replace magic-edit postMessage identifiers with hf-preview/hf-parent
- Rename debug-magic-edit-timeline.ts to debug-timeline.ts
- Replace "Motion Cut" with "HyperFrames" in Timeline comments
- Fix studio/CLI references to nonexistent archive package
  (use local data/projects/ dir, stub render proxy)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

packages/engine/src/utils/parityContract.ts

@@ -0,0 +1,35 @@
+export const MEDIA_VISUAL_STYLE_PROPERTIES = [
+  "width",
+  "height",
+  "top",
+  "left",
+  "right",
+  "bottom",
+  "inset",
+  "object-fit",
+  "object-position",
+  "z-index",
+  "opacity",
+  "visibility",
+  "filter",
+  "mix-blend-mode",
+  "backdrop-filter",
+  "border-radius",
+  "overflow",
+  "clip-path",
+  "mask",
+  "mask-image",
+  "mask-size",
+  "mask-position",
+  "mask-repeat",
+  "transform",
+  "transform-origin",
+  "box-sizing",
+] as const;
+
+export function quantizeTimeToFrame(timeSeconds: number, fps: number): number {
+  const safeFps = Number.isFinite(fps) && fps > 0 ? fps : 30;
+  const safeTime = Number.isFinite(timeSeconds) && timeSeconds > 0 ? timeSeconds : 0;
+  const frameIndex = Math.floor(safeTime * safeFps + 1e-9);
+  return frameIndex / safeFps;
+}