vedit: render-to-review with proxy + shareable path/URL

[explicit09]

Problem

author_local_review_package (crates/core/src/review.rs, crates/core/src/tools/local_review_package.rs) currently emits a local JSON manifest only. There is no proxy render attached, and no shareable URL or self-contained zip — so the "render-to-review" hand-off used by Frame.io-style workflows is not yet possible.

Scope (MVP — local-first)

1. Attach a proxy render (low-bitrate H.264 ~720p) to each review package.
2. Bundle manifest + proxy + per-frame note thumbnails into a single shareable zip on disk.
3. Return a local file:// URL plus the zip path from the tool.

Layers

1. crates/core/src/review.rs / tools/local_review_package.rs — extend package shape
2. crates/render/src/job.rs — proxy render hook (reuse existing proxy pipeline if available)
3. apps/desktop/src-tauri/src/commands/ — expose the new zip path to the desktop
4. Test: review package round-trip with proxy + manifest

Out of scope here: hosted review URL service (separate issue).

References

• Gap analysis: .reference-research/pro-editing-gap-analysis/11-collaboration.md (partial [codex] harden atomic writes and checks #1)

[explicit09]

Closing as not actionable in the current repo. This issue references crates/core/src/review.rs, crates/render, and apps/desktop surfaces that are not present. Please reopen as a new issue scoped to the current crates/vedit-core and crates/vedit-cli layout if still needed.