fix: restore console input and attachment workflows

Restore durable busy Submit queues and TUI Enter delivery, expose Web Queue beside Notify, and separate the Composer toolbar from its editor without persistent success notices.

Support pasted image attachments and restore canonical Worker Session uploaded-file operations, including retention, binding, cleanup and authenticated upload context.

Validated Worker, Protocol and Session Store suites, 278 TUI tests, 59 Web tests and Svelte check. Runtime suite could not complete due to external Workdir transport timeouts.

crates/worker-runtime/src/worker_backend.rs

@@ -4980,7 +4980,7 @@ mod tests {
     }
 
     #[test]
-    fn running_worker_replays_retry_but_rejects_a_new_submit() {
+    fn running_worker_replays_retry_and_queues_a_new_submit() {
         let client = MockClient::sequential(vec![MockResponse::Hang(vec![])]);
         let runtime_base = tempfile::tempdir().unwrap();
         let cwd = tempfile::tempdir().unwrap();
@@ -5024,11 +5024,15 @@ mod tests {
 
         let mut second_input = WorkerInput::user("second");
         second_input.submission_request_id = Some("request-second".into());
-        let error = runtime
-            .send_input(&detail.worker_ref, second_input)
-            .expect_err("a new Submit must be rejected while the Worker is running");
-        assert!(error.to_string().contains("requires an idle Worker"));
-        assert!(error.to_string().contains("use Notify"));
+        let second = runtime
+            .send_input(&detail.worker_ref, second_input.clone())
+            .expect("a new Submit must queue while the Worker is running");
+        assert_eq!(
+            second.submission.as_ref().map(|ack| ack.disposition),
+            Some(protocol::SubmissionDisposition::Queued)
+        );
+        let retry = runtime.send_input(&detail.worker_ref, second_input).unwrap();
+        assert_eq!(retry.submission, second.submission);
     }
 
     #[test]