feat(members): assign team roles from the tournament registration sheet

Match members by Discord username against the lineup nicknames in the
separate registration spreadsheet (TEAM_SHEET_ID) and give each their
team's role. One team per person: switching teams removes the old team
role, and a team with no Discord role yet is auto-created. Only role
names present in the sheet are ever touched, so organisation/field/base
roles are never at risk; the feature is a no-op when TEAM_SHEET_ID is
unset.

The sheet is not a single table (merged rows, stacked CS2/LoL sections
with different layouts), so it is parsed via raw-row scanning rather than
get_all_records. Citizenship markers like "(EST)" are used only as
player delimiters and discarded.

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

strings/member.py

@@ -91,6 +91,7 @@ CHECK_UI: dict[str, str] = {
     "detail_error":      "⚠️ {error}",
     "detail_nickname":   "hüüdnimi",
     "detail_roles_added": "+rollid: {roles}",
+    "detail_roles_removed": "-rollid: {roles}",
     "detail_changed":    "🔧 **{name}**: {parts}",
     "ids_filled":     "\n🔑 Täideti **{count}** puuduvat kasutaja ID-d.",
 }