Task #349: Executive Meetings PDF improvements

- Schema: add `font_color` (hex, default #000000) and `logo_object_path`
  to `executive_meeting_font_settings`. Pushed via drizzle-kit.

- PDF renderer:
  - Add `fontColor` to PdfFontPrefs (body cells only; header chrome
    and logo intentionally ignore it to preserve branding).
  - Add `rowColor` to PdfMeeting and a ROW_COLOR_FILL palette kept in
    lockstep with the on-screen swatches; deliberately stop painting
    the legacy `isHighlighted` overlay so the archived PDF reflects
    editorial state instead of the viewer's transient cursor.
  - Add optional `logo: Buffer`. Header now reserves a left-anchored
    logo box and centers the title in the remaining width; bad image
    bytes log + fall back to the no-logo layout instead of crashing.

- API route:
  - Extend fontSettingsSchema with strict #RRGGBB regex and
    /^/objects/<id>$/ regex for logoObjectPath.
  - resolveFontPrefsForUser now returns { font, logoObjectPath }.
  - loadLogoBytes downloads the brand asset via ObjectStorageService.
  - Logo only writable on the global-scope row.
  - PDF labels switched to "قائمة بأسماء حضور الاجتماعات" /
    "Meeting Attendance List" per the user's printed sample.

- Frontend (executive-meetings.tsx):
  - FontPrefs gains fontColor; FontSettingsResponse.global gains
    logoObjectPath; DEFAULT_FONT and effectiveFont updated.
  - buildFontStyle applies fontColor to on-screen rows.
  - FontSettingsSection: native color picker + hex text input;
    logo upload (PNG/JPEG) via @workspace/object-storage-web's
    useUpload, visible only at the global scope for admins.

- Locales: AR/EN keys for fontColor + logo.{label,upload,replace,
  remove,uploading,uploadFailed,globalOnly}.

- Tests: existing font-settings roundtrip extended with fontColor;
  new test rejects malformed fontColor and non-/objects logo paths.

Type-check clean for api-server and tx-os; new font-settings tests
pass. Other test failures in the suite pre-date this change.

artifacts/tx-os/src/locales/ar.json

@@ -1420,6 +1420,16 @@
       "fontSize": "حجم الخط",
       "fontWeight": "السماكة",
       "alignment": "المحاذاة",
+      "fontColor": "لون الخط",
+      "logo": {
+        "label": "شعار المؤسسة (يظهر أعلى ملف PDF)",
+        "upload": "رفع الشعار",
+        "replace": "استبدال الشعار",
+        "remove": "إزالة الشعار",
+        "uploading": "جاري الرفع...",
+        "uploadFailed": "فشل رفع الشعار",
+        "globalOnly": "يحفظ الشعار للمؤسسة بأكملها."
+      },
       "weight": {
         "regular": "عادي",
         "medium": "متوسط",