feat(ui): close the last gaps against the audit design (31/31)

check_design_parity.py reads its checklist from the audit page's own
proposals; it now reports every one of the 31 as implemented, with no
deliberate divergences left.

  * Schedule: the Kanban/Calendar drop-list became a pair of tabs, and the
    Running lane is outlined while it holds anything — dropping a card there
    starts the task for real, so it should not look like the other six.
  * Cowork: agent / routing / usage / folder moved out of the typing box into
    their own status strip beneath it, styled as status rather than a second
    toolbar. All of them stay interactive; the design's read-only strip would
    have cost features.
  * Folder: the path is written as the screen's title instead of sitting in a
    read-only text box that looked editable and cost a row.
  * GraphRAG: the second toolbar row is gone (Export joined the first), and
    the one button that relabelled itself became Đồ thị | Tin nhắn tabs, so
    the view you are NOT in is named too.
  * Settings gained the theme picker, so language / provider / theme are all
    reachable there as well as on the rail's account row.
  * Task editor: the five group boxes are grouped into three step tabs
    (Nội dung → Lịch chạy → Liên kết). All 22 fields verified present after
    the move; only the old section index is gone, replaced by the tabs.
  * The assistant dot now clears a screen's own bottom bar (Cowork's
    composer), measured from the composer's top edge in window coordinates.

Also adds .gitattributes: without it a Windows checkout records CRLF and
every file reads as fully rewritten to a Linux CI runner.

Verification: 7 check_*.py suites green, no screen clipped at 1920/1366/1280,
and no dialog scrolls sideways at 9/11/14pt.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

i18n.py

@@ -914,6 +914,11 @@ STRINGS: Dict[str, Dict[str, str]] = {
     # The title/description block at the top of the Task editor had no name
     # either — needed once the index had to list it.
     "schedtask.g_basic": {"en": "Basics", "ja": "基本", "vi": "Thông tin chung"},
+    # The three steps the editor is split into: what to do, when, and what it
+    # connects to. Each holds the same group boxes as before.
+    "schedtask.step_content": {"en": "Content", "ja": "内容", "vi": "Nội dung"},
+    "schedtask.step_schedule": {"en": "Schedule", "ja": "スケジュール", "vi": "Lịch chạy"},
+    "schedtask.step_link": {"en": "Links", "ja": "連携", "vi": "Liên kết"},
     "schedtask.g_schedule": {"en": "Schedule Setup", "ja": "スケジュール設定", "vi": "Thiết lập lịch chạy"},
     "schedtask.sched_enable": {"en": "Enable schedule", "ja": "スケジュールを有効化", "vi": "Bật lịch chạy"},
     "schedtask.f_run_at": {"en": "Run at", "ja": "実行日時", "vi": "Chạy lúc"},