test(e2e): replace node -e with printf for OSC title marker

Same root cause as the prior commit's BEL fix: CI Linux launches the
shell with PATH stripped of /usr/bin, so `node` is unresolvable and the
marker bytes never reach xterm. printf is a shell builtin and emits
the same OSC sequence.

Co-authored-by: Orca <help@stably.ai>

tests/e2e/terminal-attention.spec.ts

@@ -184,11 +184,9 @@ test.describe('Terminal attention', () => {
     // async PTY pipeline.
     await emitBell(orcaPage, activePtyId)
     const MARKER_TITLE = 'focused-tab-bell-marker'
-    await execInTerminal(
-      orcaPage,
-      activePtyId,
-      `node -e "process.stdout.write('\\u001b]0;${MARKER_TITLE}\\u0007')"`
-    )
+    // Why: printf is a shell builtin so it works even when CI launches the
+    // shell with a stripped PATH (no /usr/bin → no `node` resolvable).
+    await execInTerminal(orcaPage, activePtyId, `printf '\\033]0;${MARKER_TITLE}\\007'`)
 
     await expect
       .poll(