feat: database models and Alembic migrations — User, Recording, Transcription, Protocol, PromptTemplate, ExportFile

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

backend/app/models/transcription.py

@@ -0,0 +1,23 @@
+import uuid
+
+from sqlalchemy import ForeignKey, Interval, String, Text
+from sqlalchemy.dialects.postgresql import JSONB
+from sqlalchemy.orm import Mapped, mapped_column, relationship
+
+from app.models.base import Base, TimestampMixin, UUIDMixin
+
+
+class Transcription(UUIDMixin, TimestampMixin, Base):
+    __tablename__ = "transcriptions"
+
+    recording_id: Mapped[uuid.UUID] = mapped_column(
+        ForeignKey("recordings.id", ondelete="CASCADE"), unique=True
+    )
+    text: Mapped[str] = mapped_column(Text)
+    segments: Mapped[dict] = mapped_column(JSONB, default=list)
+    language: Mapped[str | None] = mapped_column(String(10), nullable=True)
+    whisper_model: Mapped[str] = mapped_column(String(50))
+    processing_time: Mapped[float | None] = mapped_column(nullable=True)
+
+    recording: Mapped["Recording"] = relationship(back_populates="transcription")
+    protocols: Mapped[list["Protocol"]] = relationship(back_populates="transcription")