Account export / restore-into-new-tree / delete

New account_service + endpoints under /users/me:
- GET /me/export — zip of every owned tree (account.json + media blobs).
- POST /me/import — restore a backup into NEW trees (ids remapped, media
  re-uploaded); non-destructive, never touches existing data.
- DELETE /me — soft-delete the user, their owned trees, and revoke sessions;
  guarded by retyping the account email.

Settings page wires all three (export download, restore upload, delete with
typed-email confirmation). No migration — uses existing tables + soft-delete.

52 backend tests pass (export→restore round-trip + delete guards); frontend builds.

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

backend/tests/test_account_portability.py

@@ -0,0 +1,86 @@
+"""Account export -> restore round-trip, and account deletion."""
+
+from tests.conftest import auth, register
+
+
+async def _seed(client, h):
+    tid = (await client.post("/api/v1/trees", json={"name": "Fam"}, headers=h)).json()["id"]
+    p1 = (
+        await client.post(
+            f"/api/v1/trees/{tid}/persons", json={"given": "Ada", "surname": "Lovelace"}, headers=h
+        )
+    ).json()["id"]
+    p2 = (
+        await client.post(f"/api/v1/trees/{tid}/persons", json={"given": "Kid"}, headers=h)
+    ).json()["id"]
+    await client.post(
+        f"/api/v1/trees/{tid}/relationships",
+        json={"type": "parent_child", "person_from_id": p1, "person_to_id": p2},
+        headers=h,
+    )
+    await client.post(
+        f"/api/v1/trees/{tid}/events",
+        json={"event_type": "birth", "person_id": p1, "date_value": "1815"},
+        headers=h,
+    )
+    await client.post(
+        f"/api/v1/trees/{tid}/media",
+        files={"file": ("scan.txt", b"hello", "text/plain")},
+        data={"title": "Scan", "person_id": p1},
+        headers=h,
+    )
+    return tid
+
+
+async def test_export_then_restore_roundtrip(client):
+    h = auth(await register(client, "exp@example.com"))
+    await _seed(client, h)
+
+    export = await client.get("/api/v1/users/me/export", headers=h)
+    assert export.status_code == 200
+    assert export.headers["content-type"] == "application/zip"
+    blob = export.content
+    assert blob[:2] == b"PK"  # zip magic
+
+    # Restore into new trees (non-destructive: the original stays).
+    r = await client.post(
+        "/api/v1/users/me/import",
+        files={"file": ("provenance-export.zip", blob, "application/zip")},
+        headers=h,
+    )
+    assert r.status_code == 200, r.text
+    counts = r.json()
+    assert counts["trees"] == 1 and counts["persons"] == 2
+    assert counts["events"] == 1 and counts["media"] == 1
+
+    trees = (await client.get("/api/v1/trees", headers=h)).json()
+    assert len(trees) == 2  # original + restored
+
+    # The restored tree has the people, with a working relationship and media.
+    restored = [t for t in trees if t["name"] == "Fam"][1]["id"]
+    ppl = (await client.get(f"/api/v1/trees/{restored}/persons", headers=h)).json()
+    assert {p["primary_name"] for p in ppl} == {"Ada Lovelace", "Kid"}
+    rels = (await client.get(f"/api/v1/trees/{restored}/relationships", headers=h)).json()
+    assert len(rels) == 1
+    med = (await client.get(f"/api/v1/trees/{restored}/media", headers=h)).json()
+    assert len(med) == 1 and med[0]["title"] == "Scan"
+
+
+async def test_delete_account_requires_email_then_revokes(client):
+    token = await register(client, "del@example.com")
+    h = auth(token)
+    await _seed(client, h)
+
+    # Wrong email is rejected.
+    bad = await client.request(
+        "DELETE", "/api/v1/users/me", data={"confirm_email": "nope@example.com"}, headers=h
+    )
+    assert bad.status_code == 403
+
+    ok = await client.request(
+        "DELETE", "/api/v1/users/me", data={"confirm_email": "del@example.com"}, headers=h
+    )
+    assert ok.status_code == 204
+
+    # Session is revoked — the token no longer works.
+    assert (await client.get("/api/v1/users/me", headers=h)).status_code == 401