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>

ui/task_editor_dialog.py

@@ -19,7 +19,7 @@ from PySide6.QtWidgets import (
     QCheckBox, QComboBox, QDateTimeEdit, QDialog, QDialogButtonBox, QFileDialog,
     QFormLayout, QGroupBox, QHBoxLayout, QInputDialog, QLabel, QLineEdit,
     QListWidget, QListWidgetItem, QMessageBox, QPlainTextEdit, QPushButton,
-    QScrollArea, QSpinBox, QVBoxLayout, QWidget,
+    QScrollArea, QSpinBox, QTabWidget, QVBoxLayout, QWidget,
 )
 
 from ..config import PROVIDER_LABELS
@@ -93,12 +93,11 @@ class TaskEditorDialog(QDialog):
         root = QVBoxLayout(content)
 
         # ---- basics ----------------------------------------------------
-        # Zero-height anchor: this block is a bare form, so the index needs
-        # something to scroll to.
-        self._anchor_basic = QWidget()
-        self._anchor_basic.setFixedHeight(0)
-        root.addWidget(self._anchor_basic)
-        form = QFormLayout()
+        # Held in its own widget so the whole block can be moved into a step
+        # tab below; it is a bare form, not a group box.
+        self._basic_box = QWidget()
+        form = QFormLayout(self._basic_box)
+        form.setContentsMargins(0, 0, 0, 0)
         self.title_edit = QLineEdit(self.task.get("title", ""))
         # Description is the source of truth. Its ✨ button GENERATES the Prompt
         # (Input) FROM the description — the title is just the task's label and
@@ -211,7 +210,7 @@ class TaskEditorDialog(QDialog):
         form.addRow(tr("schedtask.f_skill"), self.skill_combo)
         form.addRow(tr("schedtask.f_priority"), self.priority_combo)
         form.addRow(tr("schedtask.f_status"), self.status_combo)
-        root.addLayout(form)
+        root.addWidget(self._basic_box)
         self._main_form = form
         self._model_box = model_box
         self._on_run_kind_changed()   # apply agent/flow row visibility
@@ -433,25 +432,38 @@ class TaskEditorDialog(QDialog):
         eform.addRow("", self.approval_chk)
         root.addWidget(eg)
 
-        # Five groups in one long scroll — same problem, same fix as Settings.
-        from .widgets import section_index
-        self.section_list = section_index(scroll, [
-            (tr("schedtask.g_basic"), self._anchor_basic),
-            (tr("schedtask.g_schedule"), sg),
-            (tr("schedtask.g_input"), ig),
-            (tr("schedtask.g_dependency"), dg),
-            (tr("schedtask.g_execution"), eg),
-        ])
+        # Three steps, as tabs: Nội dung → Lịch chạy → Liên kết. The five group
+        # boxes are re-parented into three pages — none is dropped, they are
+        # grouped by the question being answered rather than stacked in one
+        # scroll where the later ones are out of sight.
+        self.step_tabs = QTabWidget()
+        self.step_tabs.setObjectName("taskSteps")
+        pages = [
+            ("schedtask.step_content", [self._basic_box, ig]),
+            ("schedtask.step_schedule", [sg]),
+            ("schedtask.step_link", [dg, eg]),
+        ]
+        self._step_keys = [key for key, _ in pages]
+        for _key, groups in pages:
+            page = QWidget()
+            pv = QVBoxLayout(page)
+            pv.setContentsMargins(4, 8, 4, 4)
+            for g in groups:
+                root.removeWidget(g)
+                pv.addWidget(g)
+            pv.addStretch(1)
+            wrap = QScrollArea()
+            wrap.setWidgetResizable(True)
+            wrap.setHorizontalScrollBarPolicy(Qt.ScrollBarAlwaysOff)
+            wrap.setWidget(page)
+            self.step_tabs.addTab(wrap, "")
         outer.removeWidget(scroll)
-        body = QHBoxLayout()
-        body.setSpacing(10)
-        body.addWidget(self.section_list)
-        body.addWidget(scroll, 1)
-        outer.insertLayout(0, body, 1)
-        # Same floor as Settings: the dialog may not be narrower than its own
-        # content at the font in use, so nothing is ever cut off sideways.
-        self.setMinimumWidth(self.section_list.width()
-                             + content.sizeHint().width() + 60)
+        scroll.setParent(None)
+        outer.insertWidget(0, self.step_tabs, 1)
+        self._retranslate_steps()
+        # Floor the width at what the widest page needs, at the font in use.
+        self.setMinimumWidth(max(p.widget().sizeHint().width()
+                                 for p in self.step_tabs.findChildren(QScrollArea)) + 60)
 
         buttons = QDialogButtonBox(QDialogButtonBox.Save | QDialogButtonBox.Cancel)
         buttons.button(QDialogButtonBox.Save).setIcon(icon("save"))
@@ -465,6 +477,11 @@ class TaskEditorDialog(QDialog):
         from .widgets import guard_wheel
         guard_wheel(self)
 
+    def _retranslate_steps(self) -> None:
+        """Name the three step tabs for the current language."""
+        for i, key in enumerate(self._step_keys):
+            self.step_tabs.setTabText(i, f"{i + 1}. {tr(key)}")
+
     def _apply_hints(self) -> None:
         """Tooltip hints on every non-obvious control, so each option explains
         itself on hover."""