Unify review core across Bun and Pi

[backnotprop]

Summary

• extract a runtime-agnostic review core for diff assembly, file-content lookup, worktree handling, and stage/unstage operations
• switch the Bun review path to the shared core and copy the same source into the Pi package at build time
• bring the Pi review server up to the shared review API surface, including diff switching, file content, drafts, uploads/images, agents, and editor annotations
• add regression coverage for the shared review core and the Pi review server endpoints

Fixes #307.

Testing

• bun test packages/shared/review-core.test.ts apps/pi-extension/server.test.ts
• bun test

Notes

• The full test run still has one unrelated pre-existing failure in packages/ui/components/diagramLanguages.test.ts because @viz-js/viz is not installed in this environment.

[backnotprop]

Code review

Found 1 issue:

1. Pi plannotator-review handler silently drops inline annotations. The review server's waitForDecision() returns { approved, feedback, annotations, agentSwitch } (line 693-699 of server.ts), but the command handler in index.ts only reads result.feedback and ignores result.annotations. Since this PR adds the full annotation API surface to the Pi review server, users can now create inline code annotations in the review UI that are accepted by the server but never forwarded to the agent — the annotations are silently lost.

plannotator/apps/pi-extension/index.ts

Lines 300 to 311 in 39cf90c

	const result = await runBrowserReview(server, ctx);
	if (result.feedback) {
	if (result.approved) {
	pi.sendUserMessage(`# Code Review\n\nCode review completed — no changes requested.`);
	} else {
	pi.sendUserMessage(`# Code Review Feedback\n\n${result.feedback}\n\nPlease address this feedback.`);
	}
	} else {
	ctx.ui.notify("Code review closed (no feedback).", "info");
	}
	},

The Bun hook server avoids this because it bakes annotations into the feedback string via exportAnnotations() before submission. The Pi handler needs equivalent logic — either call exportAnnotations() to merge annotations into the feedback text, or handle result.annotations separately.

🤖 Generated with Claude Code

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