feat(cli): add --approve-edits flag (off by default; v0.1 plumbing)

Adds the user-facing --approve-edits surface area:
- ServerConfig.approveEdits?: boolean
- bin.ts: --approve-edits commander option, plumbs into config,
  emits 'Approve edits: ENABLED' banner when on
- server.ts: logs 'Approve edits: ON|off' at startup

v0.1 stops here. The actual gating wiring (set_pou_code -> phobiCS-tui
approve, only proceed on exit 0) lands in the next commit. Landing
the surface area now keeps the user-visible CLI stable while the
internals catch up.

src/bin.ts

@@ -47,6 +47,7 @@ program
   .option('--fallback-headless', 'Fall back to headless if persistent fails', true)
   .option('--keep-alive', 'Keep CODESYS running after server stops', false)
   .option('--auto-mirror', 'Re-run mirror_export after every modifying tool so an external editor watching <projectDir>/mcp-mirror/ sees changes live', false)
+  .option('--approve-edits', 'Gate modifying MCP tools behind a phobiCS-tui y/n diff prompt', false)
   .option('--timeout <ms>', 'Default command timeout in ms', '60000')
   .option('--verbose', 'Enable verbose logging')
   .option('--debug', 'Enable debug logging (more verbose)')
@@ -197,6 +198,7 @@ if (opts.sshVersion) {
     debug: opts.debug || false,
     mode: (opts.mode === 'headless' ? 'headless' : 'persistent') as ExecutionMode,
     autoMirror: opts.autoMirror || false,
+    approveEdits: opts.approveEdits || false,
   };
 
   process.stderr.write(`Starting CODESYS MCP Server v${version}\n`);
@@ -207,6 +209,9 @@ if (opts.sshVersion) {
   if (config.autoMirror) {
     process.stderr.write(`  Auto-mirror: ENABLED (mirror_export runs after every edit)\n`);
   }
+  if (config.approveEdits) {
+    process.stderr.write(`  Approve edits: ENABLED (modifying tools will prompt via phobiCS-tui)\n`);
+  }
 
   startMcpServer(config).catch((err) => {
     process.stderr.write(`FATAL: ${err.message}\n`);

src/server.ts

@@ -726,6 +726,7 @@ export async function startMcpServer(config: ServerConfig): Promise<void> {
 
   serverLog.info(`Starting CODESYS Persistent MCP Server v0.1.0`);
   serverLog.info(`Mode: ${config.mode}`);
+  serverLog.info(`Approve edits: ${config.approveEdits ? 'ON' : 'off'}`);
   serverLog.info(`CODESYS Path: ${config.codesysPath}`);
   serverLog.info(`Profile: ${config.profileName}`);
   serverLog.info(`Workspace: ${config.workspaceDir}`);

src/types.ts

@@ -67,6 +67,12 @@ export interface ServerConfig extends LauncherConfig {
    * as a hard error -- the underlying edit already succeeded.
    */
   autoMirror: boolean;
+  /**
+   * If true, modifying tools (set_pou_code et al.) will shell out to
+   * phobiCS-tui in approve mode and only proceed on exit 0. Off by default
+   * so existing scripted flows are not regressed.
+   */
+  approveEdits?: boolean;
 }
 
 /** Script template parameters */