feat: breadcrumb hover Notion-style + nav_workspace_id sur toutes les pages

- _header.html: remplace click par hover (mouseenter/mouseleave)
  avec timer 200ms anti-flicker, cascade sous-menus au hover
- dashboard.py: ajoute nav_workspace_id à trash, library, workspace,
  gitea-workspace, local-workspace, workspaces, settings, pages/{id}
- La section du popover affiche 'Workspaces' pour Home, 'Private' pour le reste
- Les clics dans les popovers ferment le menu + naviguent

app/routers/dashboard.py

@@ -192,6 +192,9 @@ async def trash_page(request: Request, owner: str = Query(default=""), repo: str
                 "SELECT id, title, workspace FROM pages WHERE parent_section='Trash' ORDER BY updated_at DESC",
             ).fetchall()
     sidebar["trash_items"] = [{"id": r["id"], "name": r["title"] or "Untitled", "workspace": r["workspace"]} for r in rows]
+    # Pass active workspace for breadcrumb nav menu
+    ws = _get_active_workspace(request, user_id=_get_user_id(request))
+    sidebar["nav_workspace_id"] = ws["id"] if ws else 0
     template = env.get_template("trash.html")
     return template.render(**sidebar)
 
@@ -206,6 +209,15 @@ async def library_page(request: Request, owner: str = Query(default=""), repo: s
     from app.routers.board import _sidebar_data as board_sidebar
     env = Environment(loader=FileSystemLoader("app/templates"))
     sidebar = board_sidebar(request, owner, repo)
+    # Pass active workspace for breadcrumb nav menu
+    ws_key_ws = f"{owner}/{repo}" if owner and repo else ""
+    if ws_key_ws:
+        with get_conn() as conn:
+            ws_row = conn.execute("SELECT id FROM workspaces WHERE name=? AND owner_id=?", (ws_key_ws, _get_user_id(request))).fetchone()
+            sidebar["nav_workspace_id"] = ws_row["id"] if ws_row else 0
+    else:
+        ws = _get_active_workspace(request, user_id=_get_user_id(request))
+        sidebar["nav_workspace_id"] = ws["id"] if ws else 0
 
     template = env.get_template("library.html")
     return template.render(**sidebar)
@@ -447,6 +459,9 @@ async def workspace_page(request: Request):
     if not user:
         return RedirectResponse("/auth/login?provider=local", status_code=302)
     ctx = {**sidebar, "user": user}
+    # Pass active workspace for breadcrumb nav menu
+    ws = _get_active_workspace(request, user_id=_get_user_id(request))
+    ctx["nav_workspace_id"] = ws["id"] if ws else 0
     template = env.get_template("workspace.html")
     return template.render(**ctx)
 
@@ -498,6 +513,7 @@ async def gitea_workspace_page(request: Request):
         "workspace_initial": repo[0].upper() if repo else "G",
         "owner": owner,
         "repo": repo,
+        "nav_workspace_id": local_ws_id or 0,  # for breadcrumb nav menu
     }
     template = env.get_template("gitea_workspace.html")
     resp = HTMLResponse(content=template.render(**ctx))
@@ -661,6 +677,7 @@ async def local_workspace_page(request: Request, folder: int = None):
         "workspace_name": sidebar.get("active_ws_name", "My Workspace"),
         "current_folder_id": current_folder_id or 0,
         "workspace_id": ws_id or 0,
+        "nav_workspace_id": ws_id or 0,
         "breadcrumb": breadcrumb,
     }
     template = env.get_template("local_workspace.html")
@@ -1244,6 +1261,9 @@ async def workspaces_page(request: Request):
     if not user:
         return RedirectResponse("/auth/login?provider=local", status_code=302)
     ctx = {**sidebar, "user": user}
+    # Pass active workspace for breadcrumb nav menu (null on workspaces home)
+    ws = _get_active_workspace(request, user_id=_get_user_id(request))
+    ctx["nav_workspace_id"] = ws["id"] if ws else 0
     template = env.get_template("workspaces.html")
     return template.render(**ctx)
 
@@ -1346,6 +1366,9 @@ async def app_settings_page(request: Request):
     if not user:
         return RedirectResponse("/auth/login?provider=local", status_code=302)
     ctx = {**sidebar, "user": user}
+    # Pass active workspace for breadcrumb nav menu
+    ws = _get_active_workspace(request, user_id=_get_user_id(request))
+    ctx["nav_workspace_id"] = ws["id"] if ws else 0
     template = env.get_template("settings.html")
     return template.render(**ctx)