fix(ui): remove inline note spacer row

[benvinegar]

Summary

• Remove the standalone inline-note guide-cap row that rendered as an extra blank spacer after note ranges
• Drop the now-unused guide-cap planning, rendering, and height-measurement code
• Keep existing guide highlighting on covered diff rows without adding a trailing row

Testing

• bun run format:check
• bun run lint
• bun run typecheck
• bun test src/ui/diff/reviewRenderPlan.test.ts src/ui/components/ui-components.test.tsx src/ui/lib/diffSectionGeometry.test.ts
• bun test

This PR description was generated by Pi using OpenAI GPT-5

[greptile-apps]

Greptile Summary

Removes the note-guide-cap row type, which previously rendered a 1-row blank spacer with a ╵ border character after the last diff row in an inline note's covered range. All six changed files are consistent: the component, the render branch, the type union variant, the height-measurement branches, and the supporting planning helpers (buildGuideCapsByRowKey, diffRowStableKeyForSide, endGuideAfterKey) are all fully excised with no lingering references.

• reviewRenderPlan.ts: Removes the note-guide-cap union member from PlannedReviewRow, the endGuideAfterKey field from InlineVisibleNotePlacement, the two now-dead helper functions, and the cap-insertion loop inside buildReviewRenderPlan.
• PierreDiffView.tsx / AgentInlineNote.tsx: Drops the render branch and the AgentInlineNoteGuideCap component in lockstep.
• plannedReviewRows.ts / diffSectionGeometry.ts: Remove the note-guide-cap height-measurement guards; TypeScript narrows the remaining two variants (inline-note, diff-row) exhaustively in both functions.

Confidence Score: 5/5

Safe to merge — the change is a clean removal of a visual spacer row with no functional side effects.

Every reference to the removed feature has been deleted across all six files. The two remaining PlannedReviewRow variants are handled exhaustively in all height-measurement and render paths, and a targeted grep confirms no stale usages remain elsewhere in the codebase.

No files require special attention.

Important Files Changed

Filename	Overview
src/ui/components/panes/AgentInlineNote.tsx	Removes the AgentInlineNoteGuideCap component export; no remaining usages in the codebase.
src/ui/diff/PierreDiffView.tsx	Drops the note-guide-cap render branch and its import; remaining inline-note / diff-row paths are unaffected.
src/ui/diff/plannedReviewRows.ts	Removes the note-guide-cap height case (was a hardcoded 1); the two remaining variants (inline-note, diff-row) are handled correctly and TypeScript narrows cleanly after the inline-note guard.
src/ui/diff/reviewRenderPlan.ts	Removes the note-guide-cap union variant, endGuideAfterKey field, diffRowStableKeyForSide helper, buildGuideCapsByRowKey, and the cap insertion loop — cleanup is complete and the remaining logic is correct.
src/ui/diff/reviewRenderPlan.test.ts	Drops cap assertions from three tests; remaining assertions still cover guide-side propagation and range-less-note behaviour.
src/ui/lib/diffSectionGeometry.ts	Removes the note-guide-cap height branch; the local plannedRowHeight function now correctly narrows to diff-row for the measureRenderedRowHeight call.

_{Reviews (1): Last reviewed commit: "fix(ui): remove inline note guide spacer..." | Re-trigger Greptile}