feat(data): extend market data provider with charts, fundamentals, and quant analysis

Adds a stock data cache layer and indicator helpers (MA/RSI/MACD), expands
the MarketDataProvider interface with candles, fundamentals, related-data,
and quant analysis, and threads tags + source attribution through the
shared types. Updates affected agent tests.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

web/tests/report.test.ts

@@ -9,6 +9,7 @@ const watchlist: WatchStock[] = [
     display: "AAPL",
     market: "US",
     name: "Apple",
+    tags: ["core"],
     addedAt: "2026-05-11T00:00:00.000Z"
   },
   {
@@ -17,6 +18,7 @@ const watchlist: WatchStock[] = [
     display: "00700.HK",
     market: "HK",
     name: "Tencent",
+    tags: ["internet"],
     addedAt: "2026-05-11T00:00:00.000Z"
   }
 ];
@@ -51,6 +53,44 @@ const provider: MarketDataProvider = {
       peers: [{ display: "9988.HK", pe: 18 }],
       news: []
     };
+  },
+  async candles() {
+    return [];
+  },
+  async fundamentals() {
+    return [];
+  },
+  async relatedData() {
+    return {
+      sector: "Technology",
+      avgVolume20: 1_000_000,
+      volumeRatio: 1,
+      volatility20: 0.02,
+      drawdownFromHigh: 0.1,
+      relativeStrength60: 0.04,
+      support: 90,
+      resistance: 120,
+      capitalFlow: 0.1,
+      sentimentScore: 0.6,
+      newsHeat: 0.5,
+      riskFlags: [],
+      sources: []
+    };
+  },
+  async quantAnalysis() {
+    return {
+      action: "hold",
+      score: 55,
+      confidence: 0.5,
+      horizon: "1-3 months",
+      summary: "Hold",
+      factors: [
+        { name: "trend", score: 55, weight: 1, evidence: "neutral" },
+        { name: "valuation", score: 55, weight: 0, evidence: "neutral" },
+        { name: "risk", score: 55, weight: 0, evidence: "neutral" }
+      ],
+      riskNotes: []
+    };
   }
 };