fix(cli): correct session show rich output Session Summary panel field labels and fields

Fixes three deviations from docs/specification.md in the agents session show
rich output Session Summary panel:

1. Renamed 'Session ID:' label to 'ID:' to match spec exactly.
2. Removed 'Namespace:' field which is not part of the spec.
3. Added 'Automation:' field sourced from session.metadata['automation_profile'],
   defaulting to '(none)' when not set.
4. Field order now matches spec: ID → Actor → Messages → Created → Updated → Automation.

Updated features/session_cli.feature to assert the corrected field labels are
present ('ID:', 'Actor:', 'Messages:', 'Created:', 'Updated:', 'Automation:')
and that the removed fields ('Session ID:', 'Namespace:') are absent.

Added 'the session CLI output should not contain' step definition to
features/steps/session_cli_steps.py to support the new negative assertions.

ISSUES CLOSED: #3040

features/steps/session_cli_steps.py

@@ -480,6 +480,13 @@ def step_output_contains(context: Context, text: str) -> None:
     )
 
 
+@then('the session CLI output should not contain "{text}"')
+def step_output_not_contains(context: Context, text: str) -> None:
+    assert text not in context.result.output, (
+        f"Expected '{text}' NOT in output, but it was found:\n{context.result.output}"
+    )
+
+
 @then("the session CLI output should be valid JSON")
 def step_output_valid_json(context: Context) -> None:
     try: