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/infra/db/timescaledb/repositories/analysis.py

@@ -184,6 +184,7 @@ class AnalysisResultsRepository:
         start_time: datetime,
         end_time: datetime,
         field: str,
+        *, row_limit: int | None = None,
     ) -> dict[str, list[dict[str, Any]]]:
         if element_type == "node":
             table_name, id_column, valid_fields = (
@@ -214,8 +215,10 @@ class AnalysisResultsRepository:
             sql.Identifier(id_column),
             sql.Identifier(id_column),
         )
+        if row_limit is not None:
+            query += sql.SQL(" LIMIT %s")
         async with conn.cursor() as cur:
-            await cur.execute(query, (run_id, element_ids, start_time, end_time))
+            await cur.execute(query, (run_id, element_ids, start_time, end_time) + ((row_limit,) if row_limit is not None else ()))
             for row in await cur.fetchall():
                 result.setdefault(str(row["element_id"]), []).append(
                     {"time": row["time"], "value": row["value"]}