feat(docker): add dev.sh with auto-funding and ATM app setup

- Add dev.sh script for managing regtest development environment
- Implement cmd_fund to fund ATM app owner via Lightning.Pub API
- Add --fund flag to cmd_up for automatic funding on startup
- Update setup_atm_app to write VITE_APP_ID to machine .env
- Fix Electron IPC to pass appId and extensionApiUrl to renderer
- Restructure repo from nested lamassu-next/ to root

The dev.sh script now supports:
- ./dev.sh up --fund  # Start regtest and auto-fund ATM
- ./dev.sh fund       # Fund existing ATM app
- ./dev.sh status     # Show environment status
- ./dev.sh reset      # Clean restart

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

apps/machine/electron/preload.ts

@@ -0,0 +1,50 @@
+/**
+ * Electron Preload Script
+ *
+ * Exposes a secure API to the renderer process via contextBridge.
+ * This is the only way for the Vue app to communicate with the main process.
+ */
+
+import { contextBridge, ipcRenderer } from 'electron'
+
+/**
+ * Runtime configuration interface
+ * These values are read from environment variables at runtime (not build time)
+ */
+export interface RuntimeConfig {
+  relayUrl: string
+  lightningPubPubkey: string
+  lightningPubApiUrl: string
+  extensionApiUrl: string
+  atmPrivateKey: string
+  adminToken: string
+  appId: string
+  machineModel: string
+  fiatCode: string
+  validatorDevice?: string
+  dispenserDevice?: string
+  cassettes?: string
+}
+
+// Expose protected methods to renderer
+contextBridge.exposeInMainWorld('electronAPI', {
+  // Get app version
+  getVersion: (): Promise<string> => ipcRenderer.invoke('get-version'),
+
+  // Get runtime configuration (read from environment at runtime)
+  getConfig: (): Promise<RuntimeConfig> => ipcRenderer.invoke('get-config'),
+
+  // Platform info
+  platform: process.platform,
+})
+
+// Type declaration for the exposed API
+declare global {
+  interface Window {
+    electronAPI: {
+      getVersion: () => Promise<string>
+      getConfig: () => Promise<RuntimeConfig>
+      platform: NodeJS.Platform
+    }
+  }
+}