feat: add mobile application structure with emotion picker and API integration

- Added favicon and icon assets for the mobile app.
- Implemented EmotionPicker component for selecting emotions with child options.
- Created hooks for fetching emotions, feeds, and rapport data.
- Established API service for handling requests and authentication.
- Integrated Zustand for state management of user authentication.
- Defined color palette for the application.
- Set up TypeScript types for various entities including User, Emotion, and Feed.
- Configured Babel and TypeScript for the mobile project.
- Added package.json with necessary dependencies for Expo and React Native.

mobile/lib/auth-store.ts

@@ -0,0 +1,72 @@
+import { create } from 'zustand';
+import * as SecureStore from 'expo-secure-store';
+import api from './api';
+import type { Utilisateur } from '@/types';
+
+interface AuthState {
+  user: Utilisateur | null;
+  token: string | null;
+  isAuthenticated: boolean;
+  isLoading: boolean;
+  login: (email: string, password: string) => Promise<void>;
+  register: (data: {
+    nom: string;
+    prenom: string;
+    email: string;
+    password: string;
+    password_confirmation: string;
+  }) => Promise<void>;
+  logout: () => Promise<void>;
+  fetchUser: () => Promise<void>;
+  loadToken: () => Promise<void>;
+}
+
+export const useAuthStore = create<AuthState>()((set) => ({
+  user: null,
+  token: null,
+  isAuthenticated: false,
+  isLoading: true,
+
+  loadToken: async () => {
+    const token = await SecureStore.getItemAsync('cesizen_token');
+    if (token) {
+      set({ token, isAuthenticated: true, isLoading: false });
+      try {
+        const response = await api.get('/auth/me');
+        set({ user: response.data });
+      } catch {
+        await SecureStore.deleteItemAsync('cesizen_token');
+        set({ token: null, isAuthenticated: false, user: null, isLoading: false });
+      }
+    } else {
+      set({ isLoading: false });
+    }
+  },
+
+  login: async (email, password) => {
+    const response = await api.post('/auth/login', { email, password });
+    const { utilisateur, token } = response.data;
+    await SecureStore.setItemAsync('cesizen_token', token);
+    set({ user: utilisateur, token, isAuthenticated: true });
+  },
+
+  register: async (data) => {
+    const response = await api.post('/auth/register', data);
+    const { utilisateur, token } = response.data;
+    await SecureStore.setItemAsync('cesizen_token', token);
+    set({ user: utilisateur, token, isAuthenticated: true });
+  },
+
+  logout: async () => {
+    try {
+      await api.post('/auth/logout');
+    } catch {}
+    await SecureStore.deleteItemAsync('cesizen_token');
+    set({ user: null, token: null, isAuthenticated: false });
+  },
+
+  fetchUser: async () => {
+    const response = await api.get('/auth/me');
+    set({ user: response.data });
+  },
+}));