feat(server): integrate MCP queries and investigation messaging

Add project-bound OAuth MCP queries and controlled analysis with scoped evidence,
limits, timeouts and a nearby-model spatial query using EPSG:4326 inputs.
Default nearby searches to 200 meters and five results.

Integrate investigation messaging/presentation, health/readiness and typed history;
remove duplicate web search and fix online simulation and compressed baseline writes.
Include project migrations 023-025; keep local credentials and demo seeding excluded.

Validation: 319 focused pytest checks; real PostGIS temporary-table regression;
read-only Jinqian bridge radius comparison; cross-language MCP discovery/calls.

app/api/v1/endpoints/agent_messages.py

@@ -0,0 +1,101 @@
+"""Actor-private messaging APIs; the Agent verifies its session ownership."""
+from uuid import UUID
+
+from fastapi import APIRouter, Depends, HTTPException, Query
+from psycopg import AsyncConnection
+
+from app.auth.permissions import OPERATIONAL_TASK_VIEW, OPERATIONAL_TASK_WRITE, require_permission
+from app.auth.project_dependencies import ProjectContext, get_project_pg_connection
+from app.domain.domain_errors import DomainError
+from app.domain.schemas.agent_messages import (
+    AgentMessage, AgentMessageCreate, AgentMessageDelivery, AgentMessagePage, AgentMessageReply,
+)
+from app.infra.db.postgresql.agent_messages import AgentMessageRepository
+from app.services.agent_messages import AgentMessageService
+
+
+router = APIRouter(prefix="/agent-messages")
+
+
+def _service(ctx: ProjectContext, conn: AsyncConnection) -> AgentMessageService:
+    return AgentMessageService(AgentMessageRepository(conn, ctx.project_id), ctx)
+
+
+def _raise_domain(exc: DomainError):
+    raise HTTPException(status_code=exc.status, detail=exc.payload()) from exc
+
+
+@router.post("", response_model=AgentMessage, status_code=201)
+async def create_agent_message(
+    command: AgentMessageCreate,
+    ctx: ProjectContext = Depends(require_permission(OPERATIONAL_TASK_WRITE)),
+    conn: AsyncConnection = Depends(get_project_pg_connection),
+):
+    try:
+        return await _service(ctx, conn).create(command)
+    except DomainError as exc:
+        _raise_domain(exc)
+
+
+@router.get("", response_model=AgentMessagePage)
+async def list_agent_messages(
+    session_id: str = Query(min_length=1, max_length=500),
+    limit: int = Query(default=50, ge=1, le=100),
+    cursor: str | None = None,
+    pending_only: bool = False,
+    ctx: ProjectContext = Depends(require_permission(OPERATIONAL_TASK_VIEW)),
+    conn: AsyncConnection = Depends(get_project_pg_connection),
+):
+    try:
+        return await _service(ctx, conn).list_session(session_id, limit, cursor, pending_only)
+    except DomainError as exc:
+        _raise_domain(exc)
+
+
+@router.get("/pending", response_model=AgentMessagePage)
+async def list_pending_agent_messages(
+    limit: int = Query(default=50, ge=1, le=100),
+    cursor: str | None = None,
+    ctx: ProjectContext = Depends(require_permission(OPERATIONAL_TASK_VIEW)),
+    conn: AsyncConnection = Depends(get_project_pg_connection),
+):
+    try:
+        return await _service(ctx, conn).pending(limit, cursor)
+    except DomainError as exc:
+        _raise_domain(exc)
+
+
+@router.get("/{message_id}", response_model=AgentMessage)
+async def get_agent_message(
+    message_id: UUID,
+    ctx: ProjectContext = Depends(require_permission(OPERATIONAL_TASK_VIEW)),
+    conn: AsyncConnection = Depends(get_project_pg_connection),
+):
+    try:
+        return await _service(ctx, conn).get(message_id)
+    except DomainError as exc:
+        _raise_domain(exc)
+
+
+@router.post("/{message_id}/reply", response_model=AgentMessage, status_code=201)
+async def reply_agent_message(
+    message_id: UUID, command: AgentMessageReply,
+    ctx: ProjectContext = Depends(require_permission(OPERATIONAL_TASK_WRITE)),
+    conn: AsyncConnection = Depends(get_project_pg_connection),
+):
+    try:
+        return await _service(ctx, conn).reply(message_id, command)
+    except DomainError as exc:
+        _raise_domain(exc)
+
+
+@router.post("/{message_id}/delivery", response_model=AgentMessage)
+async def record_agent_message_delivery(
+    message_id: UUID, command: AgentMessageDelivery,
+    ctx: ProjectContext = Depends(require_permission(OPERATIONAL_TASK_VIEW)),
+    conn: AsyncConnection = Depends(get_project_pg_connection),
+):
+    try:
+        return await _service(ctx, conn).delivery(message_id, command)
+    except DomainError as exc:
+        _raise_domain(exc)