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/mcp/evidence-result.ts

@@ -0,0 +1,22 @@
+import type { CallToolResult } from "@modelcontextprotocol/client";
+import { queryMcpToolId } from "../runtime/product-mcp-tools.js";
+
+// The local server exposes tools only. Retain the saved Server evidence, but
+// replace its upstream-only resource link with this server's paging tool.
+export function localEvidenceResult(result: CallToolResult): CallToolResult {
+  if (result.isError || !result.content.some((item) => item.type === "resource_link" && item.uri.startsWith("tjwater://"))) return result;
+  const raw = result.structuredContent;
+  const output = raw && typeof raw === "object" && !Array.isArray(raw) ? raw as Record<string, unknown> : undefined;
+  const evidenceId = output?.evidence_id;
+  if (!output || typeof evidenceId !== "string" || !evidenceId || evidenceId.length > 160) throw new Error("Saved evidence response has no identifier");
+  const originalData = output.data && typeof output.data === "object" && !Array.isArray(output.data) ? output.data as Record<string, unknown> : {};
+  const { resource_uri: _uri, ...data } = originalData;
+  const next = { ...output,
+    data: { ...data, evidence_read: { tool: queryMcpToolId("get_task_evidence"), arguments: { evidence_id: evidenceId, limit: 20, offset: 0 } } },
+    data_gaps: [...(Array.isArray(output.data_gaps) ? output.data_gaps.filter((gap) => gap !== "Inline result abbreviated; read the saved evidence resource") : []),
+      "Inline result abbreviated; use evidence_read with a small page and select deeper data_path values when needed"],
+  };
+  return { ...result, structuredContent: next,
+    content: [{ type: "text", text: JSON.stringify(next) }, ...result.content.filter((item) => item.type !== "text" && item.type !== "resource_link")],
+  };
+}