feat: add finance module UI

- Finance.jsx: main page with tabs (Dashboard/Transactions/Analytics)
- FinanceDashboard: balance card, top categories, pie chart, daily line chart
- TransactionList: filtered list with search, type/category filters
- AddTransactionModal: bottom sheet with quick templates
- FinanceAnalytics: bar chart, donut chart, monthly trend
- finance.js: API layer
- Navigation: added Wallet icon for Finance
- App.jsx: added /finance route

Design matches Storybook mockups (glassmorphism, Deep Teal palette)

src/api/finance.js

@@ -0,0 +1,47 @@
+import client from './client'
+
+export const financeApi = {
+  // Categories
+  listCategories: async () => {
+    const res = await client.get('finance/categories')
+    return res.data
+  },
+  createCategory: async (data) => {
+    const res = await client.post('finance/categories', data)
+    return res.data
+  },
+  updateCategory: async (id, data) => {
+    const res = await client.put(`finance/categories/${id}`, data)
+    return res.data
+  },
+  deleteCategory: async (id) => {
+    await client.delete(`finance/categories/${id}`)
+  },
+
+  // Transactions
+  listTransactions: async (params = {}) => {
+    const res = await client.get('finance/transactions', { params })
+    return res.data
+  },
+  createTransaction: async (data) => {
+    const res = await client.post('finance/transactions', data)
+    return res.data
+  },
+  updateTransaction: async (id, data) => {
+    const res = await client.put(`finance/transactions/${id}`, data)
+    return res.data
+  },
+  deleteTransaction: async (id) => {
+    await client.delete(`finance/transactions/${id}`)
+  },
+
+  // Summary & Analytics
+  getSummary: async (params = {}) => {
+    const res = await client.get('finance/summary', { params })
+    return res.data
+  },
+  getAnalytics: async (params = {}) => {
+    const res = await client.get('finance/analytics', { params })
+    return res.data
+  },
+}