feat(smart-app): implement complete mobile app MVP

- App.tsx: full navigation (Auth stack + Main tabs with 5 screens)
- Auth: LoginScreen, RegisterScreen, ForgotPasswordScreen
- HomeScreen: dashboard with IoT metrics, weather widget, alerts, quick actions, sensors
- MapScreen: interactive map with layer toggles (6 layers)
- MarketplaceScreen: categories (6), products (5), search
- ChatScreen: AI chat with quick prompts (4), bot responses
- ProfileScreen: user info, stats, menu (9 items), logout
- AlertsScreen: alert list with severity, acknowledge
- SensorsScreen: sensor list with type filters (6 types), search
- ZonesScreen: zone cards with stats
- SettingsScreen: language picker (FR/EN/ES/DE), privacy, about
- Stores: iotStore (sensors, zones, alerts), notificationStore, uiStore + i18n
- Hooks: useSensors, useAlerts, useNotifications, useLocation
- Components: Card, Button, LoadingSpinner, ErrorBoundary, Header
- Services: iotService, notificationService (with axios API client)
- Utils: formatters (temp, AQI, noise, dates), validators (email, password, IBAN)
- Theme: colors.ts with full design system (Blue Ocean palette)
- Ditto: fixed MongoDB connection, new JWT secrets, official gateway image

smart-app-city/frontend/node_modules/yaml/dist/parse/cst-visit.d.ts

@@ -0,0 +1,39 @@
+import type { BlockMap, BlockSequence, CollectionItem, Document, FlowCollection } from './cst';
+export type VisitPath = readonly ['key' | 'value', number][];
+export type Visitor = (item: CollectionItem, path: VisitPath) => number | symbol | Visitor | void;
+/**
+ * Apply a visitor to a CST document or item.
+ *
+ * Walks through the tree (depth-first) starting from the root, calling a
+ * `visitor` function with two arguments when entering each item:
+ *   - `item`: The current item, which included the following members:
+ *     - `start: SourceToken[]` – Source tokens before the key or value,
+ *       possibly including its anchor or tag.
+ *     - `key?: Token | null` – Set for pair values. May then be `null`, if
+ *       the key before the `:` separator is empty.
+ *     - `sep?: SourceToken[]` – Source tokens between the key and the value,
+ *       which should include the `:` map value indicator if `value` is set.
+ *     - `value?: Token` – The value of a sequence item, or of a map pair.
+ *   - `path`: The steps from the root to the current node, as an array of
+ *     `['key' | 'value', number]` tuples.
+ *
+ * The return value of the visitor may be used to control the traversal:
+ *   - `undefined` (default): Do nothing and continue
+ *   - `visit.SKIP`: Do not visit the children of this token, continue with
+ *      next sibling
+ *   - `visit.BREAK`: Terminate traversal completely
+ *   - `visit.REMOVE`: Remove the current item, then continue with the next one
+ *   - `number`: Set the index of the next step. This is useful especially if
+ *     the index of the current token has changed.
+ *   - `function`: Define the next visitor for this item. After the original
+ *     visitor is called on item entry, next visitors are called after handling
+ *     a non-empty `key` and when exiting the item.
+ */
+export declare function visit(cst: Document | CollectionItem, visitor: Visitor): void;
+export declare namespace visit {
+    var BREAK: symbol;
+    var SKIP: symbol;
+    var REMOVE: symbol;
+    var itemAtPath: (cst: Document | CollectionItem, path: VisitPath) => CollectionItem | undefined;
+    var parentCollection: (cst: Document | CollectionItem, path: VisitPath) => BlockMap | BlockSequence | FlowCollection;
+}