feat: pinpoint mode for point-and-click annotations

[backnotprop]

Summary

• Adds a Pinpoint input method as an alternative to drag-to-select text
• Hover over any block or inline element to see a dashed outline + label tooltip
• Click to auto-select the element's text, then the existing annotation flow takes over (toolbar/comment/redline)
• Input method (Drag/Pinpoint) is orthogonal to annotation action mode (Selection/Comment/Redline)
• Persisted via cookie like other settings

New files

• blockTargeting.ts — target resolution (inlines, table cells, list items, code blocks, full blocks)
• usePinpoint.ts — hover/click state machine, bridges to web-highlighter via fromRange()
• PinpointOverlay.tsx — dashed outline + label badge overlay
• InputMethodToggle.tsx — Drag/Pinpoint segmented toggle
• inputMethod.ts — cookie-based persistence

Test plan

• Toggle to Pinpoint mode → cursor becomes crosshair
• Hover headings, paragraphs, bold text, inline code, links → outline + label appears
• Click text element → annotation toolbar appears (selection mode)
• Click in comment mode → comment popover opens directly
• Click in redline mode → auto-deletion annotation created
• Click code block → comment popover (same as existing hover toolbar)
• Click existing annotation highlight → selects it in panel
• Switch back to Drag → normal text selection works
• Toggle persists across page reloads

🤖 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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