fix: size DataView list columns by the table's own width (#1713)

* fix: size DataView list columns by the table's own width

The list grid was built from every column, so columns hidden below md/lg
left empty tracks and the visible cells landed under the wrong headers.
Each width now gets a template of only its visible columns (CSS variables
+ container queries on the table, so a narrow panel counts, not the window),
the header uses the same gap as the rows, and rows use a minimum height so
wrapped cells no longer overlap.

* test: wait for the title bar offset effect before asserting

The bar shows once getTitleBarVisible resolves, but --termix-titlebar-height
is set in a later passive effect, so reading it right after findByText raced
(3-5 of 40 runs under load, on main too).

* chore: rerun CI against dev-26.10.6

src/ui/tests/shell/TitleBar.test.tsx

@@ -46,7 +46,8 @@ describe("TitleBar", () => {
     installBridge();
     render(<TitleBar />);
     expect(await screen.findByText("Termix")).toBeTruthy();
-    expect(heightVar()).toBe("40px");
+    // The offset is set in an effect that can run after the bar shows up.
+    await waitFor(() => expect(heightVar()).toBe("40px"));
   });
 
   it("stays hidden in windows without the app-drawn bar", async () => {