fix(ui): align editor appearance across all five bindings - #359

Summary

Unify the uploaded-deck editor appearance across React, Vue, Angular, Svelte and Vanilla, using React as the reference. This continues #342 after the upload landing changes in #354.

• Centralize editor metrics, scoped CSS and Home ribbon artwork in pptx-viewer-shared.
• Align split New Slide buttons, icon spacing, caret placement, tab underline, disabled backgrounds, inspector cards, notes and viewport fit.
• Reuse pptx-ui-select for both font fields in all five bindings, with 120px family and 64px size widths and the agreed 12px/18px typography.
• Align thumbnail selection, 3px markers, number colors and 8px frame spacing.
• Dock the Vanilla theme editor at Design > Edit Theme in the React position.

Review repairs

• Both React font fields now use the existing native custom-element adapter. Regression tests cover disabled/value resync, callback replacement and native listener cleanup under React 18 and 19.
• Reduce shared size-field inner padding so 40.5 remains visible within the fixed 64px field. The five-binding first-screen checks assert no clipping or adjacent-control movement.
• Remove font-baseline-dependent extra height from Home control wrappers; check the same 28px rows with system and Arial font metrics.
• Correct scaled row-boundary hit detection in Vue, Svelte and Vanilla so table-cell selection is not mistaken for a resize gesture. React and Angular use explicit handles; all five table accessibility flows are covered.
• Read each generated fixture's actual first-slide layout for master/template workflows, preserving the saved-layout and artwork assertions. Core sources and these fixture generators are unchanged from the previous base.
• Await thumbnail transitions before asserting final colors, address the actual shadow comboboxes, and inventory each custom form control once while still traversing migrated command roots.
• Record the selected canvas element's native animation-start event before clicking Preview. The 500ms effect had already finished before a busy runner sampled its style; recording actual playback preserves the in-place animation assertion through cleanup.
• Integrate upstream main a1549a09, retaining its Slide Show, Help, Record and Subtitle Settings migrations. Update the affected SSR and Angular translation test harnesses, React Help/boolean-attribute assertions, and write-back mock isolation. Wait for controlled checkbox state to be committed before checking the saved deck, and measure visible ribbon groups.
• Complete all four locale dictionaries for the three new subtitle-setting strings and regenerate the customization reference for accessibility.subtitleLanguage. Existing dictionary and documentation completeness assertions are retained.
• Read Record command labels and group captions from their rendered shadow DOM in the React and Vue localization tests. Retain the complete localized/English label comparisons, disabled states and recording callback assertions.

Verification after the latest upstream integration

• Root bun run build and bun run typecheck; React 18 type checking.
• Complete shared coverage suite: 10,901 passed and 3 skipped. Complete locales coverage suite: 35 passed.
• Complete React 19 and React 18 coverage suites: 7,527 passed each. Complete Vue coverage suite: 3,158 passed. React 18 type checking passed after the coverage run.
• Rebuilt locales, checked their types, and validated all 20 packed locale subpaths across the five bindings, including ESM, CommonJS, NodeNext and Bundler declarations.
• Focused font, toolbar, Record and Subtitle Settings regressions: React 19 and React 18 175 passed each; Angular 24; Vue 13; Svelte 12; Vanilla 42.
• Latest-base browser verification: all 60 first-screen, ribbon-inventory, animation-preview, Record and Subtitle Settings cases passed across the five bindings without retries or skips.

Earlier verification of the PR changes

• Root lint, format checking, E2E neutrality, commit hooks and git diff --check.
• Packed core and five isolated binding consumers; all five published-type and external-Yjs checks.
• CI script tests in a shallow checkout: 123 passed, 1 skipped.
• All eight complete CI coverage suites on the preceding upstream base: 37,268 passed and 3 skipped. This includes both React 18 and 19 and all five bindings.
• Browser rerun against all five existing services: all 285 cases across 13 affected specs passed without failures, retries or skips. This covers first-screen parity, font changes, ribbon inventory, master/template edits, table selection, Help/Slide Show migration and persisted settings.
• Animation Preview playback and enabled-state checks: 10 additional cases passed across all five bindings without retries.

Local checks use macOS and Node 24.19; hosted CI uses Ubuntu and Node 22. The React 18 local coverage run is serial. Browser checks use the existing contributor services with webServer: [].

Commit organization

All five bindings, shared UI, related tests and design notes are in one Conventional Commit, authored and committed as Euan Zhu.