fix: resolve build errors in pass_mgr, pcexec, and safe-restart

- Fix Go syntax error: use BoolVar for --username flag instead of string
- Fix TypeScript type errors: filter undefined values from process.env
- Fix TypeScript type error: add type assertion for fetch response
- Add .gitignore to exclude node_modules and build outputs

pcexec/src/index.ts

@@ -164,10 +164,19 @@ async function replacePassMgrGets(command: string): Promise<{ command: string; p
  */
 export async function pcexec(command: string, options: PcExecOptions = {}): Promise<PcExecResult> {
   // Set up environment with workspace/agent info
-  const env: Record<string, string> = {
-    ...process.env,
-    ...options.env,
-  };
+  const env: Record<string, string> = {};
+  
+  // Copy process.env, filtering out undefined values
+  for (const [key, value] of Object.entries(process.env)) {
+    if (value !== undefined) {
+      env[key] = value;
+    }
+  }
+  
+  // Merge options.env
+  if (options.env) {
+    Object.assign(env, options.env);
+  }
   
   if (process.env.AGENT_WORKSPACE) {
     env.AGENT_WORKSPACE = process.env.AGENT_WORKSPACE;
@@ -284,10 +293,19 @@ export function pcexecSync(command: string, options: PcExecOptions = {}): PcExec
   const { execSync } = require('child_process');
   
   // Set up environment
-  const env: Record<string, string> = {
-    ...process.env,
-    ...options.env,
-  };
+  const env: Record<string, string> = {};
+  
+  // Copy process.env, filtering out undefined values
+  for (const [key, value] of Object.entries(process.env)) {
+    if (value !== undefined) {
+      env[key] = value;
+    }
+  }
+  
+  // Merge options.env
+  if (options.env) {
+    Object.assign(env, options.env);
+  }
   
   if (process.env.AGENT_WORKSPACE) {
     env.AGENT_WORKSPACE = process.env.AGENT_WORKSPACE;