fix(app): keep the command palette at a fixed height (#58939)

Co-authored-by: vimtor <vimtor@users.noreply.github.com>

Author: opencode-agent[bot]

packages/app/e2e/regression/command-palette.spec.ts

@@ -232,3 +232,19 @@ test("navigation replaces commands without retaining disposed owners", async ({
   )
   expect(warnings).toEqual([])
 })
+
+test("keeps the same height as the number of results changes", async ({ page }) => {
+  const { dialog, input } = await openCommandPalette(page)
+  const container = page.locator('[data-component="dialog-v2"] [data-slot="dialog-container"]')
+  const height = async () => (await container.boundingBox())?.height
+  const initial = await height()
+  expect(initial).toBe(480)
+
+  await input.fill("copy session")
+  await expect(dialog.getByRole("option")).toHaveCount(1)
+  expect(await height()).toBe(initial)
+
+  await input.fill("zzzz no palette match")
+  await expect(dialog.getByText("No results found")).toBeVisible()
+  expect(await height()).toBe(initial)
+})

packages/app/src/shell/commands/dialog.css

@@ -2,18 +2,10 @@
   overflow: hidden;
 }
 
-/* Anchor to the top edge of where a centered 480px-tall dialog would sit, so the
-   top stays put while the content-driven height grows and shrinks. */
-[data-component="dialog-v2"]:has(.command-palette) {
-  align-items: flex-start;
-}
-
+/* Keep a fixed height so the dialog does not resize as results change while typing. */
 [data-component="dialog-v2"]:has(.command-palette) [data-slot="dialog-container"] {
   width: min(calc(100vw - 24px), 640px);
-  height: auto;
-  min-height: 280px;
-  max-height: min(calc(100vh - 96px), 480px);
-  margin-top: max(48px, calc((100vh - 480px) / 2));
+  height: min(calc(100vh - 96px), 480px);
   border-radius: 12px;
   background: var(--v2-background-bg-base);
   box-shadow: var(--v2-elevation-floating);