Migrate PdfCraft to egui 0.37 with reconciled platform and editor behavior

Preserve current main, pin the reviewed forks, and cover hidden input,
IME lifecycle, bidi rendering, persisted settings, and editor geometry.

Repository gates pass; native/browser acceptance and paired app performance
remain explicitly open for human review.

docs/gaps.md

@@ -1,6 +1,6 @@
 # Where PdfCraft falls short of Acrobat Pro
 
-> **Last reviewed:** 2026-10-20 · **Last updated:** 2026-10-20 · **Change:** minor (gap 6 #3673: Character encoding CJK mapping routes corrected; no readiness re-estimate)
+> **Last reviewed:** 2026-10-25 · **Last updated:** 2026-10-25 · **Change:** minor (gaps 5 and 14 current state: native release Hans face via LXGW WenKai Lite; Arabic logical catalog, explicit RTL direction and mirrored stock chrome, with native/browser/IME workflows unqualified; no readiness re-estimate)
 
 > **Last reviewed:** 2026-10-15 · **Last updated:** 2026-10-19 · **Change:** minor (gap 2: composite fonts with `/ToUnicode /Identity-H` read as Unicode, hayro-interpret patch 44; estimates unchanged) · **Target:** Adobe Acrobat Pro (Acrobat DC, continuous track 26.002.21931, macOS)
 > **Last reviewed:** 2026-10-17 · **Last updated:** 2026-10-17 · **Change:** minor (gap 6: #2662 redaction audit counts a cover over one word of a long line; estimates unchanged) · **Target:** Adobe Acrobat Pro (Acrobat DC, continuous track 26.002.21931, macOS)
@@ -37,7 +37,7 @@ update the numbers.
 |---|---|---|---|---|
 | 2 | Rendering is borrowed and its fidelity unmeasured | feature, spec | 110–190 | [pdf-spec-parity.md](pdf-spec-parity.md) |
 | 3 | Editing existing text is fragile on real files | feature | 100–180 | [target-app-parity.md](target-app-parity.md) |
-| 5 | Chinese UI shows missing-glyph boxes in releases | localization | 6–12 | [localization-parity.md](localization-parity.md) |
+| 5 | Chinese UI lacks a web glyph face | localization | 6–12 | [localization-parity.md](localization-parity.md) |
 | 6 | Open-issue backlog of wrong results in shipped features | stability | 45–80 | this file |
 | 7 | OCR reads only unaccented Latin | feature | 40–75 | [file-format-parity.md](file-format-parity.md) |
 | 8 | Office export weak, Office import absent | file format | 55–100 | [file-format-parity.md](file-format-parity.md) |
@@ -46,7 +46,7 @@ update the numbers.
 | 11 | Accessibility: checker only, no tagging tools | feature | 40–70 | [target-app-parity.md](target-app-parity.md) |
 | 12 | No measured fidelity harness against Acrobat | quality | (in 2) | [target-app-parity.md](target-app-parity.md) |
 | 13 | Performance budgets and lazy loading of very large files | performance | 25–45 | this file |
-| 14 | Arabic not mirrored; no Hindi, Indonesian, Korean | localization | 25–45 | [localization-parity.md](localization-parity.md) |
+| 14 | Arabic RTL unqualified end to end; no Hindi, Indonesian, Korean | localization | 25–45 | [localization-parity.md](localization-parity.md) |
 | 15 | Forms: JavaScript object model, actions, submit, XFA depth | feature | 40–75 | [pdf-spec-parity.md](pdf-spec-parity.md) |
 | 16 | UI precision gaps (multi-select move, rulers, accelerators, windows) | UI/UX | 30–60 | [ui-parity.md](ui-parity.md) |
 | 17 | Certificate security and other protect gaps | feature, spec | 15–30 | [pdf-spec-parity.md](pdf-spec-parity.md) |
@@ -117,18 +117,19 @@ update the numbers.
   how a document looks.
 - **Estimate:** 100–180 h (the longest feature pole, M7). **Doc:** [target-app-parity.md](target-app-parity.md).
 
-### 5. Chinese UI shows missing-glyph boxes in releases
+### 5. Chinese UI lacks a web glyph face
 
-- **Missing:** a Simplified Chinese (`Hans`) UI face in release builds and a working fallback.
+- **Missing:** a Simplified Chinese (`Hans`) UI face in the web build and a working fallback. Native release builds embed LXGW WenKai Lite from the pinned craft-fonts native Simplified Chinese manifest.
 - **Evidence:** [#826](https://github.com/storytold/pdfcraft/issues/826),
   [#688](https://github.com/storytold/pdfcraft/issues/688),
   [#728](https://github.com/storytold/pdfcraft/issues/728),
   [#758](https://github.com/storytold/pdfcraft/issues/758),
-  [#689](https://github.com/storytold/pdfcraft/issues/689) (Flatpak). craft-fonts has Noto Sans
-  CJK SC, but at 16.4 MB it is too large to embed whole; the interface needs a cut of it
-  (storytold/craft-libs#213).
-- **Impact:** the second-largest language group sees a broken interface although the catalog is 97%
-  translated.
+  [#689](https://github.com/storytold/pdfcraft/issues/689) (Flatpak) predate the native face; the
+  web build still embeds only BIZ UDPGothic Regular plus the small Arabic, Hebrew, Thai and Devanagari faces.
+  craft-fonts has Noto Sans CJK SC, but at 16.4 MB it is too large to embed whole; a web face needs
+  a cut of it (storytold/craft-libs#213).
+- **Impact:** the second-largest language group sees a broken interface in the web build although
+  the catalog is 97% translated.
 - **Estimate:** 6–12 h (cut CJK faces through craft-fonts-build plus the fallback chain). **Doc:**
   [localization-parity.md](localization-parity.md).
 
@@ -305,14 +306,18 @@ update the numbers.
   to edit.
 - **Estimate:** 25–45 h. **Doc:** this file.
 
-### 14. Arabic not mirrored; no Hindi, Indonesian, Korean
+### 14. Arabic RTL unqualified end to end; no Hindi, Indonesian, Korean
 
-- **Missing:** a right-to-left layout (panels, menus, alignment), bidirectional text in the text
-  layout itself (wrapping, typed text); catalogs for Hindi, Indonesian and Korean (Acrobat ships
-  Korean; it ships Arabic in its Middle East edition; it ships none of Hindi or Indonesian).
+- **Missing:** end-to-end qualification of right-to-left interface workflows on native platforms
+  and in the browser (typed RTL text, IME composition, clipboard/selection and complex multi-line
+  bidirectional text); catalogs for Hindi, Indonesian and Korean (Acrobat ships Korean; it ships
+  Arabic in its Middle East edition; it ships none of Hindi or Indonesian). The logical catalog,
+  explicit right-to-left label direction and mirrored stock chrome are implemented and
+  unit-tested; complex RTL workflows are not yet accepted.
   Vietnamese ships as a catalog (`vi`, 100% of the current localizable union) but stays `partial`
   like other non-English languages (no translated help; engine/OS details stay English).
-- **Evidence:** [localization.md](localization.md) §Arabic; `misc.rtl-ui` planned.
+- **Evidence:** [localization.md](localization.md) §Arabic; `misc.rtl-ui` planned (end-to-end
+  qualification pending).
 - **Estimate:** 25–45 h (Arabic RTL 20–35, three catalogs 8–12 plus review). **Doc:**
   [localization-parity.md](localization-parity.md).
 
@@ -398,6 +403,7 @@ update the numbers.
 
 | Date | Change | Summary |
 |---|---|---|
+| 2026-10-25 | minor | Gaps 5 and 14 current state: native release builds embed LXGW WenKai Lite for Simplified Chinese, while the web build has no Hans face; Arabic catalogs stay logical with explicit RTL label direction and mirrored stock chrome, while native/browser RTL input, IME and complex workflows remain unqualified. Estimates unchanged. |
 | 2026-10-19 | minor | Gap 2: a Type 0 font whose `/ToUnicode` is the name `/Identity-H` or `/Identity-V` (WSCAD) reads its codes as Unicode, so such pages have text to select, find and edit (hayro-interpret patch 44, `view.render-cid-fonts`). Estimates unchanged. |
 | 2026-10-15 | minor | Gap 21: the side-by-side view had already shipped; the Compare panel filters text changes and visual differences. Estimate 10–20 h → 8–16 h |
 | 2026-10-20 | minor | Gap 6 #3673: Character encoding accepts Identity-H/V with Adobe CJK collections, or a predefined non-Identity CMap; negative and indirect-reference regressions and a read-only automation test passed after failing before the fix. Per-glyph validation and embedded-font extraction remain separate. Scores and estimates unchanged. |