feat: unify XR pane interactions

[comfuture]

Summary

• replace header/content/six-dot interaction splits with one whole-pane move target plus explicit dismiss and hand-scroll child actions
• add viewer-local controller intent classification with sticky neutral/free/depth modes, continuous accelerated depth movement, safe distance clamps, and stable manual layout identity
• route active-pane scrolling through only the right xr-standard primary thumbstick with a dead zone and frame-delta scaling
• add per-source preferred-input tracking, direct fingertip pane dragging, remote pinch movement, accelerated fingertip scroll controls, and complete source/joint/pane-loss cleanup
• centralize grab finalization so only meaningful movement persists manual placement, while touch/squeeze no-ops restore the automatic position and select/pinch taps retain focus behavior
• move active, hover, grab, and overflow feedback into independent world-depth-sorted geometry while keeping content canvas rendering invariant
• expose exact wrapped viewport metrics, preserve live-tail/manual-reading behavior, and add deterministic kitchen-sink overflow/depth fixtures plus updated controller/hand documentation
• normalize content render signatures to the effective clamped viewport line, finalize newly hidden grabs before dropping ownership, and reconcile all remaining interaction state against currently visible panes

Commits

• 8c13579 feat: unify XR pane interactions
• a461a64 docs: update XR pane controls
• 16ae0fa fix: avoid persisting no-op XR grabs
• 9877cde fix: stabilize XR pane scroll state
• cff26e0 fix: finalize hidden XR pane grabs

Validation

• GitHub Actions CI/validate passed on head cff26e0
• corepack pnpm --dir packages/webxr exec vitest run test/panel-interaction.test.ts (26 focused tests passed)
• corepack pnpm --dir packages/webxr exec vitest run test/panel-view.test.ts test/panel-interaction.test.ts (35 focused tests passed)
• corepack pnpm --filter @codori/webxr test (133 tests passed before the final focused review fix; current CI reruns the complete suite)
• corepack pnpm --filter @codori/webxr typecheck
• git diff --check
• render-spy regressions prove fractional sub-line scrolling does not rerender, rounded-line crossings do, bounds remain stable, and body/layout changes still recompute viewport metrics
• hidden-pane regressions prove visible-to-hidden transitions finalize meaningful grabs exactly once, restore no-op grabs, stop thumbstick scrolling, clear active/grab/hand-scroll ownership, retain stored positions when shown again, and leave unrelated visible pane positions untouched
• grab-finalization regressions cover normal-only fingertip withdrawal, sub-epsilon source loss, a small meaningful in-plane touch drag, and exactly-once persistence after meaningful source-loss movement
• earlier implementation validation also passed corepack pnpm --filter @codori/webxr lint and corepack pnpm --filter @codori/webxr build (with the existing Vite large-chunk advisory)
• deterministic non-immersive kitchen-sink browser QA covered independent active chrome, top/bottom overflow triangles, reduced-effects static affordances, and an overlapping near/far pane pair with the far pane active; no browser console warnings or errors were observed
• render-spy regression confirms active/hover/grab transitions do not invoke content-canvas rendering, and the content/chrome objects share world-depth render ordering

Known device-validation boundary

No real controller or hand-tracking headset was available in this environment. Controller profiles/axes, physical intent feel, refresh-rate behavior, direct fingertip contact, native versus synthesized hand events, and status-window policy on device still require the issue's recorded-headset smoke test. The implementation and browser QA do not claim physical headset validation.

Closes #143

[chatgpt-codex-connector]

💡 Codex Review

Here are some automated review suggestions for this pull request.

Reviewed commit: 16ae0fa3ed

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".

[comfuture]

@codex review
Review head: 9877cdea41f7f1b41e97947a4a07b800d1c0d0b1

Focus only on the review fixes: effective rounded/clamped viewport signatures under fractional scrolling, and visible-pane reconciliation/scroll ownership when an active or grabbed pane becomes overflow-hidden.

[chatgpt-codex-connector]

💡 Codex Review

Here are some automated review suggestions for this pull request.

Reviewed commit: 9877cdea41

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".

[comfuture]

@codex review
Review head: cff26e06cc563ed5adde3306c00a2919b400422c

Focus only on hidden-pane grab finalization ordering: meaningful and no-op grabs must finalize exactly once before visible-ID reconciliation clears ownership, without recursive refresh or unrelated pane mutation.

[chatgpt-codex-connector]

Codex Review: Didn't find any major issues. Swish!

Reviewed commit: cff26e06cc

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".