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/browser/dist/parse/cst-visit.js

@@ -0,0 +1,97 @@
+const BREAK = Symbol('break visit');
+const SKIP = Symbol('skip children');
+const REMOVE = Symbol('remove item');
+/**
+ * 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.
+ */
+function visit(cst, visitor) {
+    if ('type' in cst && cst.type === 'document')
+        cst = { start: cst.start, value: cst.value };
+    _visit(Object.freeze([]), cst, visitor);
+}
+// Without the `as symbol` casts, TS declares these in the `visit`
+// namespace using `var`, but then complains about that because
+// `unique symbol` must be `const`.
+/** Terminate visit traversal completely */
+visit.BREAK = BREAK;
+/** Do not visit the children of the current item */
+visit.SKIP = SKIP;
+/** Remove the current item */
+visit.REMOVE = REMOVE;
+/** Find the item at `path` from `cst` as the root */
+visit.itemAtPath = (cst, path) => {
+    let item = cst;
+    for (const [field, index] of path) {
+        const tok = item?.[field];
+        if (tok && 'items' in tok) {
+            item = tok.items[index];
+        }
+        else
+            return undefined;
+    }
+    return item;
+};
+/**
+ * Get the immediate parent collection of the item at `path` from `cst` as the root.
+ *
+ * Throws an error if the collection is not found, which should never happen if the item itself exists.
+ */
+visit.parentCollection = (cst, path) => {
+    const parent = visit.itemAtPath(cst, path.slice(0, -1));
+    const field = path[path.length - 1][0];
+    const coll = parent?.[field];
+    if (coll && 'items' in coll)
+        return coll;
+    throw new Error('Parent collection not found');
+};
+function _visit(path, item, visitor) {
+    let ctrl = visitor(item, path);
+    if (typeof ctrl === 'symbol')
+        return ctrl;
+    for (const field of ['key', 'value']) {
+        const token = item[field];
+        if (token && 'items' in token) {
+            for (let i = 0; i < token.items.length; ++i) {
+                const ci = _visit(Object.freeze(path.concat([[field, i]])), token.items[i], visitor);
+                if (typeof ci === 'number')
+                    i = ci - 1;
+                else if (ci === BREAK)
+                    return BREAK;
+                else if (ci === REMOVE) {
+                    token.items.splice(i, 1);
+                    i -= 1;
+                }
+            }
+            if (typeof ctrl === 'function' && field === 'key')
+                ctrl = ctrl(item, path);
+        }
+    }
+    return typeof ctrl === 'function' ? ctrl(item, path) : ctrl;
+}
+
+export { visit };