Note editor sidebar, full-doc assist, persistent drafts, version history

NoteEditorView: two-column sidebar layout (project/milestone/tags/assist
always visible), removed assist toggle button, InlineAssistPanel removed.

Writing assist: whole_doc mode rewrites entire document; DiffView.vue
replaces editor during review showing full-document diff. Scope dropdown
in sidebar switches between whole-document and section modes.

Persistent drafts: migration 0022 adds note_drafts (UNIQUE per note+user)
and note_versions (max 20, auto-pruned) tables. Draft saved after generation
completes, restored on editor mount, cleared on accept/reject. Version
snapshot created automatically whenever note body changes on save.

HistoryPanel.vue: version list + DiffView modal, restore button writes
body back to editor.

Config: OLLAMA_NUM_CTX default raised to 65536; assist num_predict now
tracks Config.OLLAMA_NUM_CTX instead of a hardcoded 4096.

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

src/fabledassistant/models/note_version.py

@@ -0,0 +1,31 @@
+from datetime import datetime, timezone
+
+from sqlalchemy import DateTime, ForeignKey, Integer, Text
+from sqlalchemy.orm import Mapped, mapped_column
+
+from fabledassistant.models import Base
+
+
+class NoteVersion(Base):
+    __tablename__ = "note_versions"
+
+    id: Mapped[int] = mapped_column(primary_key=True)
+    note_id: Mapped[int] = mapped_column(Integer, ForeignKey("notes.id", ondelete="CASCADE"))
+    user_id: Mapped[int] = mapped_column(Integer, ForeignKey("users.id", ondelete="CASCADE"))
+    body: Mapped[str] = mapped_column(Text)
+    title: Mapped[str] = mapped_column(Text, default="")
+    created_at: Mapped[datetime] = mapped_column(
+        DateTime(timezone=True), default=lambda: datetime.now(timezone.utc)
+    )
+
+    def to_dict(self, include_body: bool = True) -> dict:
+        d: dict = {
+            "id": self.id,
+            "note_id": self.note_id,
+            "user_id": self.user_id,
+            "title": self.title,
+            "created_at": self.created_at.isoformat(),
+        }
+        if include_body:
+            d["body"] = self.body
+        return d