Initial commit: MyMidas personal finance tracker

Full-stack self-hosted finance app with FastAPI backend and React frontend.

Features:
- Accounts, transactions, budgets, investments with GBP base currency
- CSV import with auto-detection for 10 UK bank formats
- ML predictions: spending forecast, net worth projection, Monte Carlo
- 7 selectable themes (Obsidian, Arctic, Midnight, Vault, Terminal, Synthwave, Ledger)
- Receipt/document attachments on transactions (JPEG, PNG, WebP, PDF)
- AES-256-GCM field encryption, RS256 JWT, TOTP 2FA, RLS, audit log
- Encrypted nightly backups + key rotation script
- Mobile-responsive layout with bottom nav

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/app/db/models/investment_transaction.py

@@ -0,0 +1,29 @@
+import uuid
+from datetime import date, datetime
+from decimal import Decimal
+
+from sqlalchemy import Date, DateTime, ForeignKey, LargeBinary, Numeric, String
+from sqlalchemy.dialects.postgresql import UUID
+from sqlalchemy.orm import Mapped, mapped_column, relationship
+
+from app.db.base import Base
+
+
+class InvestmentTransaction(Base):
+    __tablename__ = "investment_transactions"
+
+    id: Mapped[uuid.UUID] = mapped_column(UUID(as_uuid=True), primary_key=True, default=uuid.uuid4)
+    user_id: Mapped[uuid.UUID] = mapped_column(UUID(as_uuid=True), ForeignKey("users.id", ondelete="CASCADE"), nullable=False, index=True)
+    holding_id: Mapped[uuid.UUID] = mapped_column(UUID(as_uuid=True), ForeignKey("investment_holdings.id"), nullable=False, index=True)
+    transaction_id: Mapped[uuid.UUID | None] = mapped_column(UUID(as_uuid=True), ForeignKey("transactions.id"), nullable=True)
+    type: Mapped[str] = mapped_column(String(20), nullable=False)  # buy|sell|dividend|split|merger|transfer_in|transfer_out|fee
+    quantity: Mapped[Decimal] = mapped_column(Numeric(30, 10), nullable=False)
+    price: Mapped[Decimal] = mapped_column(Numeric(20, 8), nullable=False)
+    fees: Mapped[Decimal] = mapped_column(Numeric(20, 8), default=0, nullable=False)
+    total_amount: Mapped[Decimal] = mapped_column(Numeric(20, 8), nullable=False)
+    currency: Mapped[str] = mapped_column(String(10), nullable=False)
+    date: Mapped[date] = mapped_column(Date, nullable=False, index=True)
+    notes_enc: Mapped[bytes | None] = mapped_column("notes", LargeBinary, nullable=True)
+    created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), nullable=False)
+
+    holding: Mapped["InvestmentHolding"] = relationship(back_populates="investment_transactions", lazy="noload")  # type: ignore[name-defined]