feat: dynamic toolset generation for plugin platforms

Plugin platforms now get full toolset support without any entries in
toolsets.py.

tools_config._get_platform_tools(): Falls back to 'hermes-<name>'
  when the platform isn't in the static PLATFORMS dict. No more
  KeyError for plugin platforms.

toolsets.resolve_toolset(): Auto-generates a toolset for plugin
  platforms (hermes-<name>) containing _HERMES_CORE_TOOLS plus any
  tools the plugin registered into a matching toolset name. This means
  a plugin can call ctx.register_tool(toolset='irc', ...) and those
  tools will be included in the hermes-irc toolset automatically.

webhook.py: Registry-aware cross-platform delivery.
run_agent.py: Platform hints from plugin registry.
IRC adapter: Token lock + platform hint.
Removed dead token-empty-warning extension.
Updated docs.

toolsets.py

@@ -564,6 +564,27 @@ def resolve_toolset(name: str, visited: Set[str] = None) -> List[str]:
     # Get toolset definition
     toolset = get_toolset(name)
     if not toolset:
+        # Auto-generate a toolset for plugin platforms (hermes-<name>).
+        # Gives them _HERMES_CORE_TOOLS plus any tools the plugin registered
+        # into a toolset matching the platform name.
+        if name.startswith("hermes-"):
+            platform_name = name[len("hermes-"):]
+            try:
+                from gateway.platform_registry import platform_registry
+                if platform_registry.is_registered(platform_name):
+                    plugin_tools = set(_HERMES_CORE_TOOLS)
+                    try:
+                        from tools.registry import registry
+                        plugin_tools.update(
+                            e.name for e in registry._tools.values()
+                            if e.toolset == platform_name
+                        )
+                    except Exception:
+                        pass
+                    return list(plugin_tools)
+            except Exception:
+                pass
+
         return []
 
     # Collect direct tools