feat: Add InvestorInsightCache model and implement caching for investor insights

app/db/models.py

@@ -311,3 +311,24 @@ class ProjectTable(Base, TimestampMixin):
     companies = relationship(
         "CompanyTable", secondary=project_company_association, back_populates="projects"
     )
+
+
+class InvestorInsightCache(Base, TimestampMixin):
+    __tablename__ = "investor_insight_cache"
+
+    id = Column(Integer, primary_key=True, index=True)
+    investor_id = Column(
+        Integer, ForeignKey("investors.id"), nullable=False, unique=True
+    )
+
+    # Cached insights
+    investment_pattern_analysis = Column(Text, nullable=False)
+    market_position = Column(Text, nullable=False)
+
+    # Cache management
+    last_refreshed = Column(
+        DateTime(timezone=True), server_default=func.now(), nullable=False
+    )
+
+    # Relationship to investor
+    investor = relationship("InvestorTable")