feat: add quick payment action and improve copy button UX

Mini App Home Screen:
- Add 'Record Payment' button to utilities and rent period cards
- Pre-fill payment amount with member's share (rentShare/utilityShare)
- Modal dialog with amount input and currency display
- Toast notifications for copy and payment success/failure feedback

Copy Button Improvements:
- Increase spacing between icon and text (4px → 8px)
- Add hover background and padding for better touch target
- Green background highlight when copied (in addition to icon color change)
- Toast notification appears when copying any value

Backend:
- Add /api/miniapp/payments/add endpoint for quick payments
- Payment notifications sent to 'reminders' topic in Telegram
- Include member name, payment type, amount, and period in notification

Files:
- New: apps/miniapp/src/components/ui/toast.tsx
- Modified: apps/miniapp/src/routes/home.tsx, apps/miniapp/src/index.css,
  apps/miniapp/src/theme.css, apps/miniapp/src/i18n.ts,
  apps/bot/src/miniapp-billing.ts, apps/bot/src/server.ts

Quality Gates: ✅ format, lint, typecheck, build, test

Co-authored-by: Qwen-Coder <qwen-coder@alibabacloud.com>

apps/miniapp/src/components/ui/toast.tsx

@@ -0,0 +1,50 @@
+import { Show, createEffect, onCleanup } from 'solid-js'
+
+import { cn } from '../../lib/cn'
+
+export interface ToastOptions {
+  message: string
+  type?: 'success' | 'info' | 'error'
+  duration?: number
+}
+
+export interface ToastState {
+  visible: boolean
+  message: string
+  type: 'success' | 'info' | 'error'
+}
+
+const toastVariants = {
+  success: 'toast--success',
+  info: 'toast--info',
+  error: 'toast--error'
+}
+
+export function Toast(props: { state: ToastState; onClose: () => void }) {
+  let timeoutId: ReturnType<typeof setTimeout> | undefined
+
+  createEffect(() => {
+    if (props.state.visible) {
+      timeoutId = setTimeout(
+        () => {
+          props.onClose()
+        },
+        props.state.type === 'error' ? 4000 : 2000
+      )
+    }
+  })
+
+  onCleanup(() => {
+    if (timeoutId) {
+      clearTimeout(timeoutId)
+    }
+  })
+
+  return (
+    <Show when={props.state.visible}>
+      <div role="status" aria-live="polite" class={cn('toast', toastVariants[props.state.type])}>
+        <span class="toast__message">{props.state.message}</span>
+      </div>
+    </Show>
+  )
+}