ux: show 'Initializing agent...' on first message (#4086)

Display a brief status message before the heavy agent initialization
(OpenAI client setup, tool loading, memory init, etc.) so users
aren't staring at a blank screen for several seconds.

Only prints when self.agent is None (first use or after model switch).

Closes #4060

Co-authored-by: SHL0MS <SHL0MS@users.noreply.github.com>

cli.py

@@ -5597,6 +5597,8 @@ class HermesCLI:
             self.agent = None
 
         # Initialize agent if needed
+        if self.agent is None:
+            _cprint(f"{_DIM}Initializing agent...{_RST}")
         if not self._init_agent(
             model_override=turn_route["model"],
             runtime_override=turn_route["runtime"],