fix: proper error handling and --force flag for create commands

- Add global error handler: clean messages instead of stack traces
- Add --force flag to create server/secret/project: updates on 409 conflict
- Strip null values and template-only fields from --from-template payload
- Add tests: 409 handling, --force update, null-stripping from templates

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/cli/src/index.ts

@@ -14,7 +14,7 @@ import { createClaudeCommand } from './commands/claude.js';
 import { createProjectCommand } from './commands/project.js';
 import { createBackupCommand, createRestoreCommand } from './commands/backup.js';
 import { createLoginCommand, createLogoutCommand } from './commands/auth.js';
-import { ApiClient } from './api-client.js';
+import { ApiClient, ApiError } from './api-client.js';
 import { loadConfig } from './config/index.js';
 import { loadCredentials } from './auth/index.js';
 import { resolveNameOrId } from './commands/shared.js';
@@ -143,5 +143,21 @@ const isDirectRun =
   import.meta.url === `file://${process.argv[1]}`;
 
 if (isDirectRun) {
-  createProgram().parseAsync(process.argv);
+  createProgram().parseAsync(process.argv).catch((err: unknown) => {
+    if (err instanceof ApiError) {
+      let msg: string;
+      try {
+        const parsed = JSON.parse(err.body) as { error?: string; message?: string };
+        msg = parsed.error ?? parsed.message ?? err.body;
+      } catch {
+        msg = err.body;
+      }
+      console.error(`Error: ${msg}`);
+    } else if (err instanceof Error) {
+      console.error(`Error: ${err.message}`);
+    } else {
+      console.error(`Error: ${String(err)}`);
+    }
+    process.exit(1);
+  });
 }