feat(agent): unify MCP tools and adopt Responses delivery

Move project and host queries into native MCP with host-owned OAuth/context,
while retaining memory, skills, actions and publication plugins. Add nearby-model
queries and explicit chat/task/learning model defaults.

Adopt Responses HTTP/SSE and native steer/queue inbox delivery, preserving scoped
session ownership, pending input edits and investigation communication.

Disable local-provider discovery: Server /health allowed native vLLM to probe
/v1/models on port 8000. A native before/after regression prevents recurrence.

Validation: 170 focused Bun tests; service/plugin typechecks; native discovery,
provider-discovery and input-inbox smoke checks; no paid model inference.

src/runtime/mcp-config.ts

@@ -78,6 +78,7 @@ export function mcpLocalEnvironment(parent: NodeJS.ProcessEnv, explicit: Record<
 export const mcpSessionPolicySchema = z.object({
   mode: z.enum(["interactive", "readonly", "disabled"]),
   readonly_tools: z.array(z.string()),
+  query_tools: z.array(z.string()).default([]),
 }).strict();
 export type McpSessionPolicy = z.infer<typeof mcpSessionPolicySchema>;
 export const mcpServerStatusSchema = z.object({