feat: implement dashboard ban overview (Stage 5)

- Add ban_service reading fail2ban SQLite DB via read-only aiosqlite
- Add geo_service resolving IPs via ip-api.com with 10k in-memory cache
- Add GET /api/dashboard/bans and GET /api/dashboard/accesses endpoints
- Add TimeRange, DashboardBanItem, DashboardBanListResponse, AccessListItem,
  AccessListResponse models in models/ban.py
- Build BanTable component (Fluent UI DataGrid) with bans/accesses modes,
  pagination, loading/error/empty states, and ban-count badges
- Build useBans hook managing time-range and pagination state
- Update DashboardPage: status bar + time-range toolbar + tab switcher
- Add 37 new backend tests (ban service, geo service, dashboard router)
- All 141 tests pass; ruff/mypy --strict/tsc --noEmit clean

frontend/src/types/ban.ts

@@ -0,0 +1,113 @@
+/**
+ * TypeScript interfaces mirroring the backend ban Pydantic models.
+ *
+ * `backend/app/models/ban.py` — dashboard dashboard sections.
+ */
+
+// ---------------------------------------------------------------------------
+// Time-range selector
+// ---------------------------------------------------------------------------
+
+/** The four supported time-range presets for dashboard views. */
+export type TimeRange = "24h" | "7d" | "30d" | "365d";
+
+/** Human-readable labels for each time-range preset. */
+export const TIME_RANGE_LABELS: Record<TimeRange, string> = {
+  "24h": "Last 24 h",
+  "7d": "Last 7 days",
+  "30d": "Last 30 days",
+  "365d": "Last 365 days",
+} as const;
+
+// ---------------------------------------------------------------------------
+// Ban-list table item
+// ---------------------------------------------------------------------------
+
+/**
+ * A single row in the dashboard ban-list table.
+ *
+ * Mirrors `DashboardBanItem` from `backend/app/models/ban.py`.
+ */
+export interface DashboardBanItem {
+  /** Banned IP address. */
+  ip: string;
+  /** Jail that issued the ban. */
+  jail: string;
+  /** ISO 8601 UTC timestamp of the ban. */
+  banned_at: string;
+  /** First matched log line (context for the ban), or null. */
+  service: string | null;
+  /** ISO 3166-1 alpha-2 country code, or null if unknown. */
+  country_code: string | null;
+  /** Human-readable country name, or null if unknown. */
+  country_name: string | null;
+  /** Autonomous System Number string, e.g. "AS3320", or null. */
+  asn: string | null;
+  /** Organisation name associated with the IP, or null. */
+  org: string | null;
+  /** How many times this IP was banned. */
+  ban_count: number;
+}
+
+/**
+ * Paginated ban-list response from `GET /api/dashboard/bans`.
+ *
+ * Mirrors `DashboardBanListResponse` from `backend/app/models/ban.py`.
+ */
+export interface DashboardBanListResponse {
+  /** Ban items for the current page. */
+  items: DashboardBanItem[];
+  /** Total number of bans in the selected time window. */
+  total: number;
+  /** Current 1-based page number. */
+  page: number;
+  /** Maximum items per page. */
+  page_size: number;
+}
+
+// ---------------------------------------------------------------------------
+// Access-list table item
+// ---------------------------------------------------------------------------
+
+/**
+ * A single row in the dashboard access-list table.
+ *
+ * Each row represents one matched log line (failure attempt) that
+ * contributed to a ban.
+ *
+ * Mirrors `AccessListItem` from `backend/app/models/ban.py`.
+ */
+export interface AccessListItem {
+  /** IP address of the access event. */
+  ip: string;
+  /** Jail that recorded the access. */
+  jail: string;
+  /** ISO 8601 UTC timestamp of the ban that captured this access. */
+  timestamp: string;
+  /** Raw matched log line. */
+  line: string;
+  /** ISO 3166-1 alpha-2 country code, or null. */
+  country_code: string | null;
+  /** Human-readable country name, or null. */
+  country_name: string | null;
+  /** ASN string, or null. */
+  asn: string | null;
+  /** Organisation name, or null. */
+  org: string | null;
+}
+
+/**
+ * Paginated access-list response from `GET /api/dashboard/accesses`.
+ *
+ * Mirrors `AccessListResponse` from `backend/app/models/ban.py`.
+ */
+export interface AccessListResponse {
+  /** Access items for the current page. */
+  items: AccessListItem[];
+  /** Total number of access events in the selected window. */
+  total: number;
+  /** Current 1-based page number. */
+  page: number;
+  /** Maximum items per page. */
+  page_size: number;
+}