major update

app/providers/protocol.py

@@ -7,7 +7,7 @@ transfer data between providers and the service layer.
 
 from __future__ import annotations
 
-from dataclasses import dataclass
+from dataclasses import dataclass, field
 from datetime import date, datetime
 from typing import Protocol
 
@@ -39,6 +39,8 @@ class SentimentData:
     confidence: int  # 0-100
     source: str
     timestamp: datetime
+    reasoning: str = ""
+    citations: list[dict[str, str]] = field(default_factory=list)  # [{"url": ..., "title": ...}]
 
 
 @dataclass(frozen=True, slots=True)
@@ -51,6 +53,7 @@ class FundamentalData:
     earnings_surprise: float | None
     market_cap: float | None
     fetched_at: datetime
+    unavailable_fields: dict[str, str] = field(default_factory=dict)
 
 
 # ---------------------------------------------------------------------------