fix: stop rejecting unlisted models, accept with warning instead

* fix: use session_key instead of chat_id for adapter interrupt lookups

monitor_for_interrupt() in _run_agent was using source.chat_id to query
the adapter's has_pending_interrupt() and get_pending_message() methods.
But the adapter stores interrupt events under build_session_key(source),
which produces a different string (e.g. 'agent:main:telegram:dm' vs '123456').

This key mismatch meant the interrupt was never detected through the
adapter path, which is the only active interrupt path for all adapter-based
platforms (Telegram, Discord, Slack, etc.). The gateway-level interrupt
path (in dispatch_message) is unreachable because the adapter intercepts
the 2nd message in handle_message() before it reaches dispatch_message().

Result: sending a new message while subagents were running had no effect —
the interrupt was silently lost.

Fix: replace all source.chat_id references in the interrupt-related code
within _run_agent() with the session_key parameter, which matches the
adapter's storage keys.

Also adds regression tests verifying session_key vs chat_id consistency.

* debug: add file-based logging to CLI interrupt path

Temporary instrumentation to diagnose why message-based interrupts
don't seem to work during subagent execution. Logs to
~/.hermes/interrupt_debug.log (immune to redirect_stdout).

Two log points:
1. When Enter handler puts message into _interrupt_queue
2. When chat() reads it and calls agent.interrupt()

This will reveal whether the message reaches the queue and
whether the interrupt is actually fired.

* fix: accept unlisted models with warning instead of rejecting

validate_requested_model() previously hard-rejected any model not found
in the provider's API listing. This was too aggressive — users on higher
plan tiers (e.g. Z.AI Pro/Max) may have access to models not shown in
the public listing (like glm-5 on coding endpoints).

Changes:
- validate_requested_model: accept unlisted models with a warning note
  instead of blocking. The model is saved to config and used immediately.
- Z.AI setup: always offer glm-5 in the model list regardless of whether
  a coding endpoint was detected. Pro/Max plans support it.
- Z.AI setup detection message: softened from 'GLM-5 is not available'
  to 'GLM-5 may still be available depending on your plan tier'

tests/test_cli_model_command.py

@@ -31,7 +31,7 @@ class TestModelCommand:
         assert cli_obj.model == "anthropic/claude-sonnet-4.5"
         save_mock.assert_called_once_with("model.default", "anthropic/claude-sonnet-4.5")
 
-    def test_invalid_model_from_api_is_rejected(self, capsys):
+    def test_unlisted_model_accepted_with_warning(self, capsys):
         cli_obj = self._make_cli()
 
         with patch("hermes_cli.models.fetch_api_models",
@@ -40,12 +40,10 @@ class TestModelCommand:
             cli_obj.process_command("/model anthropic/fake-model")
 
         output = capsys.readouterr().out
-        assert "not a valid model" in output
-        assert "Model unchanged" in output
-        assert cli_obj.model == "anthropic/claude-opus-4.6"
-        save_mock.assert_not_called()
+        assert "not found" in output or "Model changed" in output
+        assert cli_obj.model == "anthropic/fake-model"  # accepted
 
-    def test_api_unreachable_falls_back_session_only(self, capsys):
+    def test_api_unreachable_accepts_and_persists(self, capsys):
         cli_obj = self._make_cli()
 
         with patch("hermes_cli.models.fetch_api_models", return_value=None), \
@@ -53,12 +51,11 @@ class TestModelCommand:
             cli_obj.process_command("/model anthropic/claude-sonnet-next")
 
         output = capsys.readouterr().out
-        assert "session only" in output
-        assert "will revert on restart" in output
+        assert "saved to config" in output
         assert cli_obj.model == "anthropic/claude-sonnet-next"
-        save_mock.assert_not_called()
+        save_mock.assert_called_once()
 
-    def test_no_slash_model_probes_api_and_rejects(self, capsys):
+    def test_no_slash_model_accepted_with_warning(self, capsys):
         cli_obj = self._make_cli()
 
         with patch("hermes_cli.models.fetch_api_models",
@@ -67,11 +64,8 @@ class TestModelCommand:
             cli_obj.process_command("/model gpt-5.4")
 
         output = capsys.readouterr().out
-        assert "not a valid model" in output
-        assert "Model unchanged" in output
-        assert cli_obj.model == "anthropic/claude-opus-4.6"  # unchanged
-        assert cli_obj.agent is not None  # not reset
-        save_mock.assert_not_called()
+        # Model is accepted (with warning) even if not in API listing
+        assert cli_obj.model == "gpt-5.4"
 
     def test_validation_crash_falls_back_to_save(self, capsys):
         cli_obj = self._make_cli()