feat(irc): add interactive setup

feat(gateway): refine Platform._missing_ and platform-connected dispatch

Restricts plugin-name acceptance to bundled plugin scan + registry
(no arbitrary string -> enum-pollution), pulls per-platform connectivity
checks into a _PLATFORM_CONNECTED_CHECKERS lambda map with a clean
_is_platform_connected method, and adds tests covering the checker map,
plugin platform interface, and IRC setup wizard.

run_agent.py

@@ -1855,6 +1855,16 @@ class AIAgent:
             if not isinstance(_custom_providers, list):
                 _custom_providers = []
 
+        # Resolve custom_providers list once for reuse below (startup
+        # context-length override and plugin context-engine init).
+        try:
+            from hermes_cli.config import get_compatible_custom_providers
+            _custom_providers = get_compatible_custom_providers(_agent_cfg)
+        except Exception:
+            _custom_providers = _agent_cfg.get("custom_providers")
+            if not isinstance(_custom_providers, list):
+                _custom_providers = []
+
         # Check custom_providers per-model context_length
         if _config_context_length is None and _custom_providers:
             try:
@@ -1911,6 +1921,7 @@ class AIAgent:
         self._ensure_lmstudio_runtime_loaded(_config_context_length)
 
 
+
         # Select context engine: config-driven (like memory providers).
         # 1. Check config.yaml context.engine setting
         # 2. Check plugins/context_engine/<name>/ directory (repo-shipped)
@@ -4777,6 +4788,9 @@ class AIAgent:
         # Pointer to the hermes-agent skill + docs for user questions about Hermes itself.
         prompt_parts.append(HERMES_AGENT_HELP_GUIDANCE)
 
+        # Pointer to the hermes-agent skill + docs for user questions about Hermes itself.
+        prompt_parts.append(HERMES_AGENT_HELP_GUIDANCE)
+
         # Tool-aware behavioral guidance: only inject when the tools are loaded
         tool_guidance = []
         if "memory" in self.valid_tool_names:
@@ -8572,6 +8586,13 @@ class AIAgent:
         if codex_message_items:
             msg["codex_message_items"] = codex_message_items
 
+        # Codex Responses API: preserve exact assistant message items (with
+        # id/phase) so follow-up turns can replay structured items instead of
+        # flattening to plain text. This is required for prefix cache hits.
+        codex_message_items = getattr(assistant_message, "codex_message_items", None)
+        if codex_message_items:
+            msg["codex_message_items"] = codex_message_items
+
         if assistant_message.tool_calls:
             tool_calls = []
             for tool_call in assistant_message.tool_calls: