Close the remaining gaps on Project and Cowork against the wireframes

Re-read both drawings element by element rather than by eye. Five things were
still wrong.

Cowork headed itself "Cowork" — the screen's own name, which the rail already
shows — where the drawing puts the THREAD's title. The title now follows the
conversation, falling back to the screen name for a chat that has none yet;
ChatPanel notifies on load, on reset and when a title is first derived from the
opening turn.

Its files panel read "Tệp đầu ra"; every section heading in the drawings is
caps, so it matches the rail and Monitoring now.

Project kept its three-line explanation above the panes on every visit. The
drawing heads a populated screen with the title alone and gives the text to the
EMPTY state instead, which is where it is actually needed — so it shows only
when there is no project yet.

The workspace path sat as grey caption text where the drawing shows a field. A
read-only line edit looks like one and lets the path be selected and copied.

And Lưu project sat directly under the folder row; the drawing floats it at the
foot of the panel, so a stretch went in above it.

Checked against the control inventory, not just the picture: "Nén" and "Thư mục
Local…" are marked giữ nguyên tại chỗ, so they stay in the status strip even
though the drawing's status line is text only.

New check_cowork_screen; check_project_screen gains the three points. Both
mutation-tested — pinning the title back to tr("cowork.title") and making the
hint unconditional each fail.

23/23 checkers pass. The Qt teardown segfault is still around: check_no_hscroll
took it 1 run in 3, after printing its verdict.

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

tools/check_cowork_screen.py

@@ -0,0 +1,99 @@
+"""Workspace ▸ Cowork against its wireframe (section 5).
+
+The drawing heads the screen with the THREAD's title — "Gom số liệu doanh thu",
+not the word "Cowork" — with the model beside it, Skills and Cuộc trò chuyện mới
+on the right, and a caps TỆP ĐẦU RA (n) panel down the side.
+"""
+from __future__ import annotations
+
+import os
+import sys
+
+sys.stdout.reconfigure(encoding="utf-8", errors="replace")
+
+from pathlib import Path
+
+REPO = Path(__file__).resolve().parent.parent
+sys.path.insert(0, str(REPO.parent))
+sys.path.insert(0, str(Path(__file__).resolve().parent))
+os.environ.setdefault("QT_QPA_PLATFORM", "offscreen")
+
+from capture_screens import (  # noqa: E402
+    _apply_theme, _freeze_schedulers, _isolate_home, _load_fonts)
+
+
+def main() -> int:
+    sandbox = _isolate_home()
+    from PySide6.QtWidgets import QApplication
+
+    app = QApplication([])
+    _load_fonts()
+    _freeze_schedulers()
+    _apply_theme(app)
+
+    from cowork_local.config import CONFIG_DIR
+    assert str(sandbox) in str(CONFIG_DIR), f"isolation failed: {CONFIG_DIR}"
+
+    from seed_demo_data import seed
+    seed()
+
+    from cowork_local.app import MainWindow
+    from cowork_local.config import AppConfig
+    from cowork_local.core.history import list_conversations, load_conversation
+    from cowork_local.i18n import set_language, tr
+    from cowork_local.state import AppContext
+
+    set_language("vi")
+    win = MainWindow(AppContext(AppConfig.load()), user_name="local")
+    win.resize(1920, 1000)
+    win.show()
+    app.processEvents()
+    win._goto(win._ROW_WORKSPACE, win.workspace._cowork_tab_idx)
+    app.processEvents()
+    c = win.cowork
+    fails = []
+
+    # a new thread has no title yet, so the screen name stands in
+    print(f"chua mo thread: tieu de={c._title_lbl.text()!r}")
+    if not c._title_lbl.text().strip():
+        fails.append("tieu de trong khi chua mo thread")
+
+    convs = list_conversations()
+    if not convs:
+        fails.append("khong co hoi thoai de kiem")
+    else:
+        conv = load_conversation(Path(convs[0]["path"]))
+        c.load_conversation(conv)
+        app.processEvents()
+        want = conv.get("title", "")
+        print(f"sau khi mo thread: tieu de={c._title_lbl.text()!r} (thread={want!r})")
+        if want and c._title_lbl.text() != want:
+            fails.append(f"tieu de khong theo thread: {c._title_lbl.text()!r} != {want!r}")
+        if c._title_lbl.text() == tr("cowork.title") and want:
+            fails.append("tieu de van la ten man hinh")
+
+    # the files panel is a caps section carrying its own count
+    head = c.output_section.header.text()
+    print(f"pane tep dau ra: {head!r}")
+    body = head.lstrip("▾▸ ").split(" (")[0]
+    if body != body.upper():
+        fails.append(f"tieu de pane chua viet hoa: {head!r}")
+    if "(" not in head:
+        fails.append("tieu de pane khong kem so luong")
+
+    # toolbar keeps both actions the drawing shows
+    for name, btn in (("Skills", c.skills_btn), ("chat moi", c._new_btn)):
+        if not btn.isVisible():
+            fails.append(f"thieu nut {name} tren thanh cong cu")
+    print(f"nut tren thanh cong cu: {c.skills_btn.text()!r}, {c._new_btn.text()!r}")
+
+    print()
+    for f in fails:
+        print("FAIL  " + f)
+    print("PASS  man Cowork khop ban ve" if not fails else f"{len(fails)} problem(s)")
+    sys.stdout.flush()
+    os._exit(1 if fails else 0)
+
+
+if __name__ == "__main__":
+    raise SystemExit(main())