Stage 8: world map view — backend endpoint, map component, map page

- BansByCountryResponse model added to ban.py
- bans_by_country() service: parallel geo lookup via asyncio.gather,
  aggregation by ISO alpha-2 country code (up to 2 000 bans)
- GET /api/dashboard/bans/by-country endpoint in dashboard router
- 290 tests pass (5 new), ruff + mypy clean (44 files)
- isoNumericToAlpha2.ts: 249-entry ISO numeric → alpha-2 static map
- types/map.ts, api/map.ts, hooks/useMapData.ts created
- WorldMap.tsx: react-simple-maps Mercator SVG map, per-country ban
  count overlay, colour intensity scaling, country click filtering,
  GeoLayer nested-component pattern for useGeographies context
- MapPage.tsx: time-range selector, WorldMap, country filter info bar,
  summary line, companion FluentUI Table with country filter
- Frontend tsc + ESLint clean (0 errors/warnings)

frontend/src/types/map.ts

@@ -0,0 +1,31 @@
+/**
+ * TypeScript types for the world-map / bans-by-country API.
+ */
+
+/** Time-range preset for filtering queries. */
+export type TimeRange = "24h" | "7d" | "30d" | "365d";
+
+/** A single enriched ban item as returned by the by-country endpoint. */
+export interface MapBanItem {
+  ip: string;
+  jail: string;
+  banned_at: string;
+  service: string | null;
+  country_code: string | null;
+  country_name: string | null;
+  asn: string | null;
+  org: string | null;
+  ban_count: number;
+}
+
+/** Response from GET /api/dashboard/bans/by-country */
+export interface BansByCountryResponse {
+  /** ISO alpha-2 country code → ban count */
+  countries: Record<string, number>;
+  /** ISO alpha-2 country code → human-readable country name */
+  country_names: Record<string, string>;
+  /** All individual ban records in the window (up to server limit) */
+  bans: MapBanItem[];
+  /** Total ban count in the window */
+  total: number;
+}