Add soft-delete + recovery and tree-wide graph endpoints

Tree and person soft-delete + restore (owner-only for trees, editor for people) with recovery listings (?deleted=true); the worker already purges past the 30-day window. Adds tree-wide GET /relationships and /events so the family/pedigree view loads the whole graph in a few calls. 27 tests pass.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Signed-off-by: Justin Paul <justin@jpaul.me>

backend/app/services/tree_service.py

@@ -3,6 +3,7 @@ authorization basis) and an audit entry. Reads go through the privacy engine.
 """
 
 import uuid
+from datetime import UTC, datetime
 
 from sqlalchemy import select
 from sqlalchemy.ext.asyncio import AsyncSession
@@ -59,3 +60,55 @@ async def get_tree(session: AsyncSession, *, viewer_id: uuid.UUID, tree_id: uuid
     if not await privacy.can_view_tree(session, user_id=viewer_id, tree=tree):
         raise Forbidden("not permitted to view this tree")
     return tree
+
+
+async def _owned_tree(session: AsyncSession, *, actor: User, tree_id: uuid.UUID) -> Tree:
+    """Load a tree (including soft-deleted) and require the actor be its owner."""
+    tree = await BaseRepository(session, Tree).get(tree_id, include_deleted=True)
+    if tree is None:
+        raise NotFound("tree not found")
+    role = await privacy.get_membership_role(session, actor.id, tree.id)
+    if role is not MembershipRole.owner:
+        raise Forbidden("only the owner can delete or restore a tree")
+    return tree
+
+
+async def delete_tree(session: AsyncSession, *, actor: User, tree_id: uuid.UUID) -> None:
+    tree = await _owned_tree(session, actor=actor, tree_id=tree_id)
+    if tree.deleted_at is None:
+        tree.deleted_at = datetime.now(UTC)
+        record_audit(
+            session,
+            action="delete",
+            entity_type="Tree",
+            entity_id=tree.id,
+            tree_id=tree.id,
+            actor_user_id=actor.id,
+        )
+        await session.commit()
+
+
+async def restore_tree(session: AsyncSession, *, actor: User, tree_id: uuid.UUID) -> Tree:
+    tree = await _owned_tree(session, actor=actor, tree_id=tree_id)
+    if tree.deleted_at is not None:
+        tree.deleted_at = None
+        record_audit(
+            session,
+            action="restore",
+            entity_type="Tree",
+            entity_id=tree.id,
+            tree_id=tree.id,
+            actor_user_id=actor.id,
+        )
+        await session.commit()
+    return tree
+
+
+async def list_deleted_trees_for_user(session: AsyncSession, *, user: User) -> list[Tree]:
+    stmt = (
+        select(Tree)
+        .join(TreeMembership, TreeMembership.tree_id == Tree.id)
+        .where(TreeMembership.user_id == user.id, Tree.deleted_at.is_not(None))
+        .order_by(Tree.deleted_at.desc())
+    )
+    return list((await session.execute(stmt)).scalars().all())