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/chat/sessionBridge.ts

@@ -54,7 +54,7 @@ export class ChatSessionBridge {
     let sessionId = existingSessionId;
     let created = false;
     if (!sessionId) {
-      const session = await this.runtime.createSession();
+      const session = await this.runtime.createSession(undefined, requestContext);
       sessionId = session.id;
       requestContext = {
         ...requestContext,
@@ -67,7 +67,7 @@ export class ChatSessionBridge {
       sessionId,
       startedAt: Date.now(),
     };
-    const workspaceDirectory = await this.runtime.ensureSessionWorkspace?.(sessionId);
+    const workspaceDirectory = await this.runtime.ensureSessionWorkspace?.(sessionId, requestContext);
     setRuntimeSessionContext({
       workspaceDirectory,
       actorKey: requestContext.actorKey,
@@ -110,7 +110,8 @@ export class ChatSessionBridge {
       return null;
     }
 
-    await this.abortActiveRuntime(clientSessionId, sessionId);
+    try { await this.runtime.cancelPendingUserInputs?.(sessionId); }
+    finally { await this.abortActiveRuntime(clientSessionId, sessionId); }
     return {
       clientSessionId,
       sessionId,
@@ -121,6 +122,8 @@ export class ChatSessionBridge {
   async deleteSession(context: {
     clientSessionId: string;
     sessionId: string;
+    actorKey: string;
+    projectKey: string;
   }) {
     const clientSessionId = context.clientSessionId.trim();
     const sessionId = context.sessionId.trim();
@@ -129,19 +132,8 @@ export class ChatSessionBridge {
       this.abortControllers.delete(clientSessionId);
       controller.abort();
     }
-    await this.runtime.abortSession(sessionId).catch((error) => {
-      logger.warn(
-        { clientSessionId, sessionId, err: error },
-        "failed to abort runtime session",
-      );
-    });
-    await this.runtime.waitForSessionIdle(sessionId).catch((error) => {
-      logger.warn(
-        { clientSessionId, sessionId, err: error },
-        "failed while waiting for runtime session to become idle",
-      );
-    });
-    removeRuntimeSessionContext(sessionId);
+    try { await this.runtime.removeSession(sessionId, context); }
+    finally { removeRuntimeSessionContext(sessionId); }
   }
 
   private buildRequestContext(context: {