feat: named image references and annotate command

[backnotprop]

Summary

• Named image references (Feature Request: Image names for referencing in feedback #67): Replaces raw temp file paths with human-readable ImageAttachment objects ({path, name}) throughout the annotation pipeline. Users can edit names inline under thumbnails. Exported feedback uses [name] /tmp/path... format. Sharing format is backward-compatible with old URLs.
• Annotate any markdown ([Feature Request] plannotator annotate <file.md> - Annotate any markdown file #109): New plannotator annotate <file.md> CLI subcommand and /plannotator-annotate slash command. Opens any markdown file in the Plannotator annotation UI for structured feedback. Reuses the plan editor HTML with mode: "annotate" — no new build target needed.

Closes #67
Closes #109

Changed files

Area	Files	What
Types	packages/ui/types.ts	ImageAttachment interface, Annotation.images replaces .imagePaths
Server	packages/server/index.ts, review.ts	Upload returns originalName
Server	packages/server/annotate.ts (new)	Annotate server module
Server	packages/server/package.json	Export ./annotate
UI	AttachmentsButton.tsx	deriveImageName(), editable name inputs
UI	AnnotationToolbar.tsx, Viewer.tsx, AnnotationPanel.tsx	ImageAttachment[] props
Utils	parser.ts	[name] path export format
Utils	sharing.ts, useSharing.ts	Backward-compat ShareableImage type
Editor	App.tsx	annotateMode state, annotate feedback handler, UI conditionals
CLI	apps/hook/server/index.ts	annotate subcommand
Commands	apps/hook/commands/plannotator-annotate.md (new)	Claude Code slash command
OpenCode	apps/opencode-plugin/index.ts	Annotate event handler
Commands	apps/opencode-plugin/commands/plannotator-annotate.md (new)	OpenCode slash command

Test plan

• Attach image to annotation → verify editable name input appears under thumbnail
• Upload Login Mockup.png → verify default name is login-mockup
• Paste clipboard image → verify auto-name image-1
• Export diff → verify [image-name] /tmp/... format
• Open old share URL with plain imagePaths → images still load (backward compat)
• plannotator annotate README.md → browser opens → annotation tools work → Send Annotations
• /plannotator-annotate README.md → same flow via slash command
• bun run build:hook && bun run build:opencode → clean build

🤖 Generated with Claude Code

[backnotprop]

Code review

No issues found. Checked for bugs and CLAUDE.md compliance.

🤖 Generated with Claude Code

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