refactor: rename package fabledassistant -> scribe (code-only)

Renames src/fabledassistant -> src/scribe and all imports, plus the
default DB name and DB user/password (fabled -> scribe) in config +
compose. 952 refs / 154 files. Reverses the old 'internal name stays
fabledassistant' convention.

Code-only: live databases are still physically named 'fabledassistant'.
Deployed environments must set POSTGRES_DB / POSTGRES_USER (or rename the
DB) since the defaults now resolve to 'scribe'. Repo (FabledScribe), git
host (fabledsword), MCP (fabled-git) and the image name (fabledscribe)
are intentionally unchanged.

ruff check src/ clean locally; CI (typecheck + pytest) is the gate.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/scribe/models/event.py

@@ -0,0 +1,79 @@
+from datetime import datetime, timedelta, timezone
+
+from sqlalchemy import Boolean, DateTime, ForeignKey, Integer, Text
+from sqlalchemy.orm import Mapped, mapped_column
+
+from scribe.models import Base
+from scribe.models.base import SoftDeleteMixin
+
+
+class Event(Base, SoftDeleteMixin):
+    __tablename__ = "events"
+
+    id: Mapped[int] = mapped_column(primary_key=True)
+    user_id: Mapped[int] = mapped_column(
+        Integer, ForeignKey("users.id", ondelete="CASCADE")
+    )
+    project_id: Mapped[int | None] = mapped_column(
+        Integer, ForeignKey("projects.id", ondelete="SET NULL"), nullable=True
+    )
+    # iCal UID for Radicale linkage (unique per user)
+    uid: Mapped[str] = mapped_column(Text)
+    title: Mapped[str] = mapped_column(Text, default="")
+    start_dt: Mapped[datetime] = mapped_column(DateTime(timezone=True))
+    # Duration in minutes; NULL = point event with no end specified.
+    # Replaces the prior `end_dt` column (Fable #160 / migration 0043).
+    # The DB has a CHECK constraint that this is NULL or >= 0, so an
+    # event whose end is before its start is structurally inexpressible.
+    duration_minutes: Mapped[int | None] = mapped_column(Integer, nullable=True)
+    all_day: Mapped[bool] = mapped_column(Boolean, default=False)
+    description: Mapped[str] = mapped_column(Text, default="")
+    location: Mapped[str] = mapped_column(Text, default="")
+    caldav_uid: Mapped[str] = mapped_column(Text, default="")
+    color: Mapped[str] = mapped_column(Text, default="")
+    recurrence: Mapped[str | None] = mapped_column(Text, nullable=True)
+    reminder_minutes: Mapped[int | None] = mapped_column(Integer, nullable=True)
+    reminder_sent_at: Mapped[datetime | None] = mapped_column(DateTime(timezone=True), nullable=True)
+    created_at: Mapped[datetime] = mapped_column(
+        DateTime(timezone=True), default=lambda: datetime.now(timezone.utc)
+    )
+    updated_at: Mapped[datetime] = mapped_column(
+        DateTime(timezone=True),
+        default=lambda: datetime.now(timezone.utc),
+        onupdate=lambda: datetime.now(timezone.utc),
+    )
+
+    @property
+    def end_dt(self) -> datetime | None:
+        """Derived end datetime: ``start_dt + duration_minutes``.
+
+        Returns ``None`` for point events (``duration_minutes is None``).
+        Computed at access time rather than stored — a stored end was
+        the source of the "end before start" corruption that motivated
+        this redesign.
+        """
+        if self.duration_minutes is None:
+            return None
+        return self.start_dt + timedelta(minutes=self.duration_minutes)
+
+    def to_dict(self) -> dict:
+        end_dt = self.end_dt
+        return {
+            "id": self.id,
+            "user_id": self.user_id,
+            "uid": self.uid,
+            "caldav_uid": self.caldav_uid,
+            "project_id": self.project_id,
+            "title": self.title,
+            "start_dt": self.start_dt.isoformat() if self.start_dt else None,
+            "end_dt": end_dt.isoformat() if end_dt else None,
+            "duration_minutes": self.duration_minutes,
+            "all_day": self.all_day,
+            "description": self.description,
+            "location": self.location,
+            "color": self.color,
+            "recurrence": self.recurrence,
+            "reminder_minutes": self.reminder_minutes,
+            "created_at": self.created_at.isoformat() if self.created_at else None,
+            "updated_at": self.updated_at.isoformat() if self.updated_at else None,
+        }