feat(run): a Find entry on every console, not just the Run toolbar (#1764)

Console search exists (⌘F, the magnifier in a Run tab's toolbar), but a console without a
toolbar of its own — a stack-trace tab, say — offered no visible way in: the shortcut only
worked once the output had focus, and nothing said so.

Every uncontrolled ConsoleView now shows a small Find button over the output's top-right
corner, opening the same find bar (query, match count, Enter/Shift+Enter, case and regex
options). Consoles whose find bar a toolbar drives keep exactly one entry: the toolbar's.

How it was verified:
- pnpm vitest run src/features/run/findBar.test.tsx: 9 passed, including a new test that
  the button opens the find bar and focuses its input.
- pnpm typecheck.

src/features/run/Run.module.css

@@ -81,7 +81,32 @@
 
 /* Console */
 
+.consoleFindOpen {
+  position: absolute;
+  top: 6px;
+  right: 14px;
+  z-index: 2;
+  display: inline-flex;
+  align-items: center;
+  justify-content: center;
+  width: 22px;
+  height: 22px;
+  padding: 0;
+  border: none;
+  border-radius: 4px;
+  color: var(--fg-secondary);
+  background: var(--bg-toolbar);
+  opacity: 0.6;
+}
+
+.consoleFindOpen:hover,
+.consoleFindOpen:focus-visible {
+  opacity: 1;
+  color: var(--fg-primary);
+}
+
 .consoleWrap {
+  position: relative;
   flex: 1;
   display: flex;
   flex-direction: column;