fix(cli): suppress spurious 'Unknown toolsets' warning for plugin toolsets validated before registration

cli.py

@@ -5071,8 +5071,23 @@ def __init__(
             # Validate each toolset — MCP server names are resolved via
             # live registry aliases (registered during discover_mcp_tools),
             # but discovery hasn't run yet at this point, so exclude them.
+            # Same for plugin toolsets (e.g. "a2a", "spotify"): they're
+            # registered at plugin load time, which happens after this
+            # constructor runs, so "a2a" would otherwise be reported as
+            # unknown even though it loads fine moments later.
             mcp_names = set((CLI_CONFIG.get("mcp_servers") or {}).keys())
-            invalid = [t for t in toolsets if not validate_toolset(t) and t not in mcp_names]
+            plugin_ts_names = {
+                name
+                for names in (CLI_CONFIG.get("known_plugin_toolsets") or {}).values()
+                for name in (names or [])
+            }
+            invalid = [
+                t
+                for t in toolsets
+                if not validate_toolset(t)
+                and t not in mcp_names
+                and t not in plugin_ts_names
+            ]
             if invalid:
                 self._console_print(f"[bold red]Warning: Unknown toolsets: {', '.join(invalid)}[/]")