fix(t2b): no success receipt for a submit that never landed or a pane that never closed (#484, #485)

src/key-names.ts

@@ -1,13 +1,41 @@
 const CTRL_C_ALIASES = new Set(["c-c", "ctrl-c", "ctrl+c", "^c"]);
 
+// AIDEV-NOTE (#484): every one of these means "submit" to the target CLI, but
+// the delivery engine used to test `key === "return"` by exact match. A lead
+// pressing "Enter" therefore got a receipt claiming submit_attempted:false for
+// a submit that really was dispatched — a success receipt whose own fields said
+// nothing had been attempted. This set exists to make the RECEIPT truthful; it
+// deliberately does NOT rewrite the key handed to cmux. Raw "\r"/"\n" are not
+// listed: a newline is how a composer expresses shift+enter, so treating it as
+// a submit would claim an attempt the caller did not make.
+const SUBMIT_KEY_ALIASES = new Set([
+  "return",
+  "enter",
+  "kpenter",
+  "kp_enter",
+  "kp-enter",
+  "c-m",
+  "ctrl-m",
+  "ctrl+m",
+  "^m",
+]);
+
+function canonicalKeyToken(key: string): string {
+  return key.trim().toLowerCase().replace(/\s+/g, "");
+}
+
+/** True when this key name submits the composer on the target CLI. */
+export function isSubmitKey(key: string): boolean {
+  return SUBMIT_KEY_ALIASES.has(canonicalKeyToken(key));
+}
+
 export function normalizeKeyName(key: string): string {
   const trimmed = key.trim();
   if (!trimmed) {
     return trimmed;
   }
 
-  const normalized = trimmed.toLowerCase().replace(/\s+/g, "");
-  if (CTRL_C_ALIASES.has(normalized)) {
+  if (CTRL_C_ALIASES.has(canonicalKeyToken(trimmed))) {
     return "ctrl-c";
   }