feat(V2): migrazione sentiment completa (read-only, env ignored)

- exchanges/sentiment/{client,fetchers,tools}.py: SentimentClient wrapper stateless (cryptopanic_key, lunarcrush_key)
- routers/sentiment.py: 9 tool POST sotto /mcp-sentiment (news, social, funding, OI, liquidations, cointegration)
- exchanges/__init__.py: branch builder per sentiment (env ignored)
- tests/unit/exchanges/sentiment: migrato test_fetchers, scartato test_server_acl V1-only
- tests/unit/test_exchanges_builder.py: aggiunto test_build_client_sentiment_no_env_distinction
- fetchers.py: env var lookup allineato a LUNARCRUSH_KEY (con fallback LUNARCRUSH_API_KEY)

241 test passano.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/cerbero_mcp/routers/sentiment.py

@@ -0,0 +1,98 @@
+"""Router /mcp-sentiment/* — read-only data provider.
+
+Sentiment non distingue testnet/mainnet (CryptoPanic, LunarCrush e gli endpoint
+pubblici di funding/OI multi-exchange sono unici), ma manteniamo la signature
+`Environment` per uniformità con gli altri router. Tutti i tool sono READ —
+niente write, niente leverage_cap.
+"""
+from __future__ import annotations
+
+from typing import Literal
+
+from fastapi import APIRouter, Depends, Request
+
+from cerbero_mcp.client_registry import ClientRegistry
+from cerbero_mcp.exchanges.sentiment import tools as t
+from cerbero_mcp.exchanges.sentiment.client import SentimentClient
+
+Environment = Literal["testnet", "mainnet"]
+
+
+def get_environment(request: Request) -> Environment:
+    return request.state.environment
+
+
+async def get_sentiment_client(
+    request: Request, env: Environment = Depends(get_environment)
+) -> SentimentClient:
+    registry: ClientRegistry = request.app.state.registry
+    return await registry.get("sentiment", env)
+
+
+def make_router() -> APIRouter:
+    r = APIRouter(prefix="/mcp-sentiment", tags=["sentiment"])
+
+    @r.post("/tools/get_crypto_news")
+    async def _get_crypto_news(
+        params: t.GetCryptoNewsReq,
+        client: SentimentClient = Depends(get_sentiment_client),
+    ):
+        return await t.get_crypto_news(client, params)
+
+    @r.post("/tools/get_world_news")
+    async def _get_world_news(
+        params: t.GetWorldNewsReq,
+        client: SentimentClient = Depends(get_sentiment_client),
+    ):
+        return await t.get_world_news(client, params)
+
+    @r.post("/tools/get_social_sentiment")
+    async def _get_social_sentiment(
+        params: t.GetSocialSentimentReq,
+        client: SentimentClient = Depends(get_sentiment_client),
+    ):
+        return await t.get_social_sentiment(client, params)
+
+    @r.post("/tools/get_funding_rates")
+    async def _get_funding_rates(
+        params: t.GetFundingRatesReq,
+        client: SentimentClient = Depends(get_sentiment_client),
+    ):
+        return await t.get_funding_rates(client, params)
+
+    @r.post("/tools/get_funding_arb_spread")
+    async def _get_funding_arb_spread(
+        params: t.GetFundingArbSpreadReq,
+        client: SentimentClient = Depends(get_sentiment_client),
+    ):
+        return await t.get_funding_arb_spread(client, params)
+
+    @r.post("/tools/get_cross_exchange_funding")
+    async def _get_cross_exchange_funding(
+        params: t.GetCrossExchangeFundingReq,
+        client: SentimentClient = Depends(get_sentiment_client),
+    ):
+        return await t.get_cross_exchange_funding(client, params)
+
+    @r.post("/tools/get_oi_history")
+    async def _get_oi_history(
+        params: t.GetOiHistoryReq,
+        client: SentimentClient = Depends(get_sentiment_client),
+    ):
+        return await t.get_oi_history(client, params)
+
+    @r.post("/tools/get_liquidation_heatmap")
+    async def _get_liquidation_heatmap(
+        params: t.GetLiquidationHeatmapReq,
+        client: SentimentClient = Depends(get_sentiment_client),
+    ):
+        return await t.get_liquidation_heatmap(client, params)
+
+    @r.post("/tools/get_cointegration_pairs")
+    async def _get_cointegration_pairs(
+        params: t.GetCointegrationPairsReq,
+        client: SentimentClient = Depends(get_sentiment_client),
+    ):
+        return await t.get_cointegration_pairs(client, params)
+
+    return r