feat(obico): AI print-failure detection via self-hosted Obico ML API (#172)

Adds a Failure Detection tab under Settings that wires Bambuddy to a
  self-hosted Obico ml_api container — no cloud, no account, no WebSocket.
  While a print is running, the detection service periodically hands the
  printer's camera snapshot URL to the ML API and smooths scores over
  time (30-frame warmup + EWM, alpha=2/13, short/long rolling means) so
  one noisy frame can't trigger an action. When the smoothed score
  crosses HIGH, the configured action fires exactly once per print:
  notify, pause, or pause-and-cut-power (via linked smart plugs).

  - Backend: new obico_detection + obico_smoothing + obico_actions
    services, /obico/status and /obico/test-connection routes
    (SETTINGS_READ / SETTINGS_UPDATE), six obico_* AppSettings fields
    with validators for sensitivity/action/enabled_printers.
  - Frontend: FailureDetectionSettings component (enable, ML URL + test,
    sensitivity, action, poll interval, per-printer monitor list, live
    status + detection history), new sidebar tab with service-active
    bullet, toast on save.
  - Tests: 17 detection unit tests + 15 smoothing unit tests + 4
    frontend component tests.
  - Docs: README bullet, CHANGELOG entry, wiki page under Analytics,
    website features.html entry.

frontend/src/api/client.ts

@@ -925,6 +925,12 @@ export interface AppSettings {
   ldap_group_mapping: string;
   ldap_auto_provision: boolean;
   ldap_default_group: string;
+  obico_enabled: boolean;
+  obico_ml_url: string;
+  obico_sensitivity: 'low' | 'medium' | 'high';
+  obico_action: 'notify' | 'pause' | 'pause_and_off';
+  obico_poll_interval: number;
+  obico_enabled_printers: string;
 }
 
 export type AppSettingsUpdate = Partial<AppSettings>;
@@ -1832,6 +1838,37 @@ export interface LocalBackupFile {
   created_at: string;
 }
 
+export interface ObicoDetectionEvent {
+  printer_id: number;
+  task_name: string;
+  timestamp: string;
+  current_p: number;
+  score: number;
+  class: 'safe' | 'warning' | 'failure';
+  detections: number;
+}
+
+export interface ObicoStatus {
+  is_running: boolean;
+  last_error: string | null;
+  per_printer: Record<string, { class: string; frame_count: number; score: number }>;
+  thresholds: { low: number; high: number };
+  history: ObicoDetectionEvent[];
+  enabled: boolean;
+  ml_url: string;
+  sensitivity: 'low' | 'medium' | 'high';
+  action: 'notify' | 'pause' | 'pause_and_off';
+  poll_interval: number;
+  external_url_configured: boolean;
+}
+
+export interface ObicoTestConnection {
+  ok: boolean;
+  status_code: number | null;
+  body: string | null;
+  error: string | null;
+}
+
 export interface GitHubTestConnectionResponse {
   success: boolean;
   message: string;
@@ -4518,6 +4555,16 @@ export const api = {
   deleteLocalBackup: (filename: string) =>
     request<{ success: boolean; message: string }>(`/local-backup/backups/${encodeURIComponent(filename)}`, { method: 'DELETE' }),
 
+  // Obico AI failure detection
+  getObicoStatus: () =>
+    request<ObicoStatus>('/obico/status'),
+
+  testObicoConnection: (url: string) =>
+    request<ObicoTestConnection>('/obico/test-connection', {
+      method: 'POST',
+      body: JSON.stringify({ url }),
+    }),
+
   // Local Presets (OrcaSlicer imports)
   getLocalPresets: () =>
     request<LocalPresetsResponse>('/local-presets/'),