Follow-up to #717. Replaces all remaining hardcoded keybinding hints with configurable ones.
- Add pasteImage to AppAction so it can be configured in keybindings.json
- Create keybinding-hints.ts with reusable helper functions:
- editorKey(action) / appKey(keybindings, action) - get key display string
- keyHint(action, desc) / appKeyHint(kb, action, desc) / rawKeyHint(key, desc) - styled hints
- Export helpers from components/index.ts for extensions
- Update all components to use configured keybindings
- Remove now-unused getDisplayString() from KeybindingsManager and EditorKeybindingsManager
- Use keybindings.matches() instead of matchesKey() for pasteImage in custom-editor.ts
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