feat(tooling): add project init script

Add bin/init-template.mjs for bootstrapping new projects from template with placeholder replacement and auto git init.

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

bin/init-template.mjs

@@ -0,0 +1,73 @@
+#!/usr/bin/env node
+
+import fs from 'fs';
+import path from 'path';
+import { execSync } from 'child_process';
+import { fileURLToPath } from 'url';
+
+const EXCLUDE = [
+  '.git',
+  'node_modules',
+  '.next',
+  '.sisyphus',
+  'pnpm-lock.yaml',
+  'bin',
+];
+
+function copyRecursive(src, dest, replacements) {
+  const stat = fs.statSync(src);
+  if (stat.isDirectory()) {
+    if (EXCLUDE.includes(path.basename(src))) return;
+    fs.mkdirSync(dest, { recursive: true });
+    for (const entry of fs.readdirSync(src)) {
+      copyRecursive(path.join(src, entry), path.join(dest, entry), replacements);
+    }
+  } else {
+    let content = fs.readFileSync(src, 'utf-8');
+    for (const [key, value] of Object.entries(replacements)) {
+      content = content.split(key).join(value);
+    }
+    fs.writeFileSync(dest, content);
+  }
+}
+
+function main() {
+  const projectName = process.argv[2];
+
+  if (!projectName) {
+    console.error('Usage: node bin/init-template.js <project-name>');
+    process.exit(1);
+  }
+
+  const targetDir = path.resolve(process.cwd(), projectName);
+
+  if (fs.existsSync(targetDir)) {
+    console.error(`Directory already exists: ${targetDir}`);
+    process.exit(1);
+  }
+
+  const __dirname = path.dirname(fileURLToPath(import.meta.url));
+  const templateDir = path.resolve(__dirname, '..');
+
+  const replacements = {
+    'convex-next-saas': projectName,
+    'https://convex-backend.mentat.ovh': 'https://your-convex-backend.example.com',
+    'https://backend-site-olnjg91x5ervt6j6owwgnlha.mentat.ovh': 'https://your-convex-site.example.com',
+    'self-hosted-convex|01eea0ecf04bed0f70b73021564229f7f08eecff003f7294e5f9279faa4c19ffd5c501b0ac': 'self-hosted-convex|YOUR_ADMIN_KEY',
+    'http://localhost:3000': 'http://localhost:3000',
+    'SaaS Template': projectName,
+    'Create SaaS in a day!': `${projectName} — built with convex-next-saas`,
+  };
+
+  console.log(`Creating ${projectName}...`);
+  copyRecursive(templateDir, targetDir, replacements);
+
+  execSync('git init', { cwd: targetDir, stdio: 'inherit' });
+
+  console.log('Installing dependencies...');
+  execSync('pnpm install', { cwd: targetDir, stdio: 'inherit' });
+
+  console.log(`\nDone! cd ${projectName} && pnpm dev --webpack`);
+}
+
+main();