fix(web_server): preserve action exit code after reaping zombie proc

Follow-up on the zombie-reap fix: once the Popen handle is reaped and
dropped from _ACTION_PROCS, migrate the exit code/pid into _ACTION_RESULTS
so subsequent /api/actions/{name}/status polls keep reporting the real
result instead of falling back to None. The dashboard polls repeatedly,
so without this the status flips from 'exited N' to 'unknown' on the
next poll.

hermes_cli/web_server.py

@@ -1691,6 +1691,17 @@ async def get_action_status(name: str, lines: int = 200):
         exit_code = proc.poll()
         running = exit_code is None
         pid = proc.pid
+        if not running:
+            # Reap the finished child to prevent zombie accumulation.
+            try:
+                proc.wait(timeout=1)
+            except Exception:
+                pass
+            _ACTION_PROCS.pop(name, None)
+            # Preserve the result so subsequent polls keep reporting the real
+            # exit code/pid instead of falling back to None once the handle
+            # is gone.
+            _ACTION_RESULTS[name] = {"exit_code": exit_code, "pid": pid}
 
     return {
         "name": name,

tests/hermes_cli/test_web_server.py

@@ -823,6 +823,50 @@ class TestWebServerEndpoints:
         assert resp.json() == {"ok": True, "pid": 12345, "name": "hermes-update"}
         assert calls == [(["update"], "hermes-update")]
 
+    def test_finished_action_proc_is_reaped_and_removed(self):
+        """Processes that have exited are reaped via .wait() and removed
+        from _ACTION_PROCS so they do not accumulate as zombies."""
+        import hermes_cli.web_server as web_server
+
+        waited = []
+
+        class FinishedProc:
+            pid = 99999
+
+            def poll(self):
+                return 0
+
+            def wait(self, timeout=None):
+                waited.append(timeout)
+                return 0
+
+        name = "gateway-restart"
+        proc = FinishedProc()
+        web_server._ACTION_PROCS[name] = proc
+        web_server._ACTION_RESULTS.pop(name, None)
+        try:
+            status = self.client.get(f"/api/actions/{name}/status")
+            assert status.status_code == 200
+            data = status.json()
+            assert data["running"] is False
+            assert data["exit_code"] == 0
+            assert data["pid"] == 99999
+            # The proc should have been reaped and removed.
+            assert waited, "proc.wait() was not called"
+            assert name not in web_server._ACTION_PROCS
+
+            # A second poll, after the handle is gone, must still report the
+            # real exit code/pid from _ACTION_RESULTS rather than None.
+            status2 = self.client.get(f"/api/actions/{name}/status")
+            assert status2.status_code == 200
+            data2 = status2.json()
+            assert data2["running"] is False
+            assert data2["exit_code"] == 0
+            assert data2["pid"] == 99999
+        finally:
+            web_server._ACTION_PROCS.pop(name, None)
+            web_server._ACTION_RESULTS.pop(name, None)
+
     def test_get_status_filters_unconfigured_gateway_platforms(self, monkeypatch):
         import gateway.config as gateway_config
         import hermes_cli.web_server as web_server