feat(app): refine mobile diff review and wrapping preferences - #46390

Summary

• Make mobile Changes diffs edge-to-edge and square, with expanded-only sticky per-file summaries and a centered total changes count.
• Add Open file to the expanded summary and select its requested Files tab immediately, without waiting for loading or allowing delayed responses to steal selection.
• Show mobile diff line numbers and put the persisted Wrap lines preference in General settings, supporting wrapping or horizontal scrolling.
• Match the Changes header divider to mobile navigation and remove touch hover/pressed feedback from accordion headers.

Stack

1. feat(app): refine mobile shell home and settings #46388: mobile shell, Home, and settings (base v2).
2. feat(app): add mobile session panels and detail drawers #46389: mobile session views, Files, Status, and details (base feat(app): refine mobile shell home and settings #46388).
3. feat(app): refine mobile diff review and wrapping preferences #46390: mobile Changes summaries, Open file, and wrapping preferences (base feat(app): add mobile session panels and detail drawers #46389).

Merge in that order; each PR's diff and before/after evidence compare against its immediate base. Independent #46391 (touch controls/PWA) can land separately.

Sessions

• ses_fa8e8d9a1ffedn46jvXHQkVsgx: diff summaries/layout, touch header states, immediate file selection.
• ses_fa8c9b9c6ffeULe3oLIORr07X2: summary Open file, mobile line numbers and wrapping.
• ses_fa8b1e744ffe1OzY51WvOANIwC: child of the preceding session; move Wrap lines to General preferences and update regression coverage.
• ses_fa8b34988ffdpVySqqaO61cULj: final Changes header divider.

Before / After

Mobile review polish compared with its actual stacked panel base, plus desktop shared-component coverage.

Surface	Before	After
Mobile Changes: edge-to-edge square list, header divider and centered totals
Added file: summary counts, Open file action and line numbers
Deleted file: Removed summary and deletion counts
Modified file: wrapped realistic long line and line-number gutter
Scrolled review: sticky file header and new sticky summary (scrollTop 80)
Forced RTL: expanded summary and Open file action at logical end
Touch-held accordion: touch hover behavior, without CSS overrides
Corrected full-width General preferences: Wrap lines enabled (absent on base)
Corrected full-width General preferences: Wrap lines disabled (absent on base)
Horizontal diff mode after preference toggle (base honestly remains wrapped)
Horizontal code panned 180px with fixed line numbers (base remains wrapped)
Open action outcome: base stays on Changes; head selects Files and checkout.ts
Desktop real shared SessionReview story: centered totals and Collapse all sizing
Desktop real shared SessionReview accordion hover
Desktop real shared SessionReview pointer-pressed background

• Mobile Chromium touch-emulated viewport 390x844, deviceScaleFactor 1; desktop 1280x900. Light theme, English locale, identical deterministic API fixture within each pair. No source/CSS imitation or fixed-delay synchronization.
• Mobile route /server/<base64 http://127.0.0.1:4490 or :4491>/session/ses_smoke_target. Production dist served on isolated base4490/head4491; no app build or benchmark performed by capture agent.
• Original diff evidence captured against cd6e351 vs 21cc894. Corrected settings and final readiness refresh against stacked base325ba2150e/head19af7f56a4, including inherited settings-layout fix4e0db6a875. Readiness refresh replaces both collapsed images, both added-file images, and base modified/sticky images. Other correct evidence preserved.
• Base has no Wrap lines preference. Before images in preference-off and horizontal-mode pairs deliberately retain actual base UI rather than simulate the missing feature.
• Old nested Open icon opens checkout.ts but leaves Changes selected. Separate 12b-manual-files-navigation-before.png verifies that manual Files navigation reveals the opened file. New summary button selects Files automatically; both exact file identities/content asserted.
• Forced RTL uses document.dir=rtl with English copy, not a translated locale; code and paths stay LTR. Expanded action placement is visually inspected.
• Touch-held screenshot uses real CDP touchStart/touchCancel. Chromium did not expose :active for that touch event, so it is not claimed as a verified CSS active-state capture. Desktop mouse-held :active is independently asserted.
• Desktop app uses separate ReviewPanel. Desktop evidence instead uses existing production SessionReview Storybook /iframe.html?id=components-session-review--unified&viewMode=story&globals=theme:light;direction:ltr;locale:en on isolated4492/4493. Story has constant controlled open list and no onOpenChange, so desktop collapsed story is unavailable without editing source; expanded, real hover and pressed states are captured.
• All 15 raw screenshot pairs visually inspected with rendered syntax highlighting and file icons. Final refresh waits for actual shadow-DOM span styles referencing --syntax-keyword and --syntax-string plus at least three computed syntax-token colors (excluding line-number colors), and nonempty SVG use.getBBox() geometry proving external file-icon sprites are instantiated. No loading-state caveat remains for paired screenshots.
• Head raw recording review-flow-head.webm is 390x844 VP8, 1.84 seconds. No presentation sleeps; some intermediate preferences states are too fast or omitted by recorder sampling. Prefer clearly labeled review-flow-milestones-head.mp4, a 12.04-second screenshot milestone walkthrough (not a realtime recording) with asserted expansion, corrected General Wrap lines on/off, horizontal code pan, and automatic Files selection. No fabricated transitions.
• No source edits, commits, pushes, uploads or PR operations performed. Existing untracked Storybook generated declarations left untouched.

Recording

Asserted screenshot milestone walkthrough, NOT a realtime recording: expand a mobile diff, enable/disable Wrap lines in corrected General preferences, pan horizontal code, then automatically select Files and checkout.ts. Light theme, 390x844, 12.04 seconds; no fabricated transitions.

Validation

• Updated shared mobile session readiness checks to verify titlebar identity rather than the intentionally removed heading. Eighteen affected notice/history/projection regressions and the mobile line-comment regression pass after updating the selected Changes expectation.
• A full combined local E2E run was not green. After fixing mobile readiness/selection expectations, all ten remaining failures reproduced identically on clean v2: macOS keyboard assumptions in large-paste caret movement, MCP dialog shortcuts, and Shift+F10 context-menu tests. Baseline run: 10 failed, 14 passed; alternative native key probes passed. These unrelated harness fixes are excluded. Do not treat focused passes as a full-suite pass.
• Follow-up screenshot verification found and fixed a production settings CSS-cascade issue; all 16 focused stack regressions now pass, including full-width settings geometry and updated drawer/sidebar expectations.
• All four PR groups merge cleanly in an isolated integration worktree; the combined production build passes all eight mobile browser regressions and app typechecking.
• App, session-ui, and ui package typechecks pass.
• Three production-build mobile regressions pass: LTR/RTL summaries, line numbers, wrapping persistence, Open file, and delayed-loading file selection.
• All 620 app unit tests and all 166 session-ui unit tests pass.
• Pre-push full workspace typecheck passes all 33 tasks, with hooks enabled.
• Production home-to-session navigation benchmark passes before and after: stable content observation 143.1ms on the base and 168.5ms on the head. These are single machine-local samples, not statistical performance conclusions; unrelated capture activity may affect timings.
• E2E typecheck has one pre-existing error in new-session-workspace-pending.spec.ts:38 (dir on HTMLElement | SVGElement); reproduced on clean v2.
• Shared review header totals/Expand all sizing affect shared desktop consumers too; accordion pressed-background removal also affects desktop.
• Actual iOS Safari touch behavior still requires device verification.
• Original user worktree/staging and existing app/server processes were not modified or restarted. Merged CORS/icons and generated declaration artifacts are excluded.