feat(teams): add opt-in /teamsync reposition to tidy existing team roles

Creation-time placement only positions NEW team roles. Team roles made before
divider placement existed (sitting at the bottom of the role list) stayed put.

Add `reposition_team_roles(guild)` and expose it via `/teamsync reposition:true`
(off by default, so the hourly task never reorders roles on its own). It moves
each EXISTING team role under its game's divider, sheet-driven:

- a role's game/divider comes from sheets.get_game_for_team;
- roles whose team is no longer in the sheet (or game unknown) are left alone;
- idempotent: a role already within its section band (below its own divider,
  above the next divider down) is skipped, so re-runs move nothing.

Adds RepositionSummary, TEAMSYNC_UI/OPT strings, and tests.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01R6JZkyszyDFuFtk25WBbcR

tests/test_team_sync.py

@@ -273,3 +273,46 @@ def test_new_team_role_without_known_divider_is_left_in_place(monkeypatch):
     assert result.created == "NEWTEAM"             # still created, just not moved
     new_role = next(r for r in guild.roles if r.name == "NEWTEAM")
     assert new_role.position == 0                  # default, untouched
+
+
+# --- reposition_team_roles (opt-in cleanup of existing roles) ---------------
+
+def test_reposition_moves_out_of_section_roles_and_skips_placed_ones(monkeypatch):
+    cs2_div = FakeRole(100, "CS2 divider", position=20)
+    lol_div = FakeRole(200, "LoL divider", position=10)
+    genesis = FakeRole(1, "GENESIS", position=2)       # CS2 team stuck at bottom
+    pushing = FakeRole(2, "Pushing 30s", position=5)   # LoL team already in band
+    unrelated = FakeRole(3, "Moderator", position=30)  # not a team - ignored
+    guild = FakeGuild([cs2_div, lol_div, genesis, pushing, unrelated])
+
+    games = {"GENESIS": "CS2", "Pushing 30s": "LoL"}
+    monkeypatch.setattr(sheets, "all_team_names", lambda: {"GENESIS", "Pushing 30s"})
+    monkeypatch.setattr(sheets, "get_game_for_team", lambda t: games.get(t))
+    monkeypatch.setattr(config, "TEAM_DIVIDER_ROLE_IDS", {"CS2": 100, "LoL": 200})
+
+    repo = run(member_sync.reposition_team_roles(guild))
+
+    assert repo.scanned == 2                    # only the two team roles
+    assert repo.moved == 1                       # only GENESIS was out of place
+    assert repo.moves == ["GENESIS -> CS2"]
+    assert genesis.position == 20                # moved under the CS2 divider
+    assert pushing.position == 5                 # already in its band, untouched
+    assert unrelated.position == 30              # non-team role never considered
+
+
+def test_reposition_leaves_role_whose_team_is_not_in_sheet(monkeypatch):
+    cs2_div = FakeRole(100, "CS2 divider", position=20)
+    lol_div = FakeRole(200, "LoL divider", position=10)
+    ghost = FakeRole(1, "GhostTeam", position=2)   # a team role, but gone from sheet
+    guild = FakeGuild([cs2_div, lol_div, ghost])
+
+    # Team no longer registered -> not in all_team_names, so never scanned/moved.
+    monkeypatch.setattr(sheets, "all_team_names", lambda: {"GENESIS"})
+    monkeypatch.setattr(sheets, "get_game_for_team", lambda t: None)
+    monkeypatch.setattr(config, "TEAM_DIVIDER_ROLE_IDS", {"CS2": 100, "LoL": 200})
+
+    repo = run(member_sync.reposition_team_roles(guild))
+
+    assert repo.scanned == 0
+    assert repo.moved == 0
+    assert ghost.position == 2                   # left exactly where it was