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/core/config.py

@@ -1,6 +1,7 @@
 from pathlib import Path
 from typing import Optional
 from urllib.parse import quote_plus
+from pydantic import AliasChoices, Field
 from pydantic_settings import BaseSettings, SettingsConfigDict
 
 
@@ -25,6 +26,9 @@ class Settings(BaseSettings):
     TIMESCALEDB_DB_PORT: str = "5433"
     TIMESCALEDB_DB_USER: str = "postgres"
     TIMESCALEDB_DB_PASSWORD: str = "password"
+    TIMESCALEDB_REALTIME_MAX_DECOMPRESSED_TUPLES: int = Field(
+        default=1_000_000, ge=1, le=2_147_483_647,
+    )
     # Metadata Database Config (PostgreSQL)
     METADATA_DB_NAME: str = "system_hub"
     METADATA_DB_HOST: str = "localhost"
@@ -77,16 +81,19 @@ class Settings(BaseSettings):
             raise ValueError("CORS_ALLOWED_ORIGINS must list explicit origins")
         return origins
 
-    # Bocha Web Search API
-    BOCHA_API_KEY: str = ""
-    BOCHA_WEB_SEARCH_URL: str = "https://api.bochaai.com/v1/web-search"
-    BOCHA_WEB_SEARCH_TIMEOUT_SECONDS: float = 30.0
-
-    # Tianditu Geocoding API
-    TIANDITU_GEOCODER_TOKEN: str = ""
+    # One shared Tianditu key for geocoding, place search and other services.
+    TIANDITU_TOKEN: str = Field(
+        "",
+        validation_alias=AliasChoices(
+            "TIANDITU_TOKEN", "TJWATER_TIANDITU_TOKEN", "TIANDITU_GEOCODER_TOKEN"
+        ),
+    )
     TIANDITU_GEOCODER_URL: str = "https://api.tianditu.gov.cn/geocoder"
     TIANDITU_GEOCODER_TIMEOUT_SECONDS: float = 30.0
 
+    TIANDITU_SEARCH_URL: str = "https://api.tianditu.gov.cn/v2/search"
+    TIANDITU_SEARCH_TIMEOUT_SECONDS: float = 15.0
+
     @property
     def SQLALCHEMY_DATABASE_URI(self) -> str:
         db_password = quote_plus(self.DB_PASSWORD)