chore: switch to ESM-only build output

[scalvert]

Summary

• Remove CJS build format and switch to ESM-only output
• Add "type": "module" to package.json for proper ESM support
• Update all export paths from .mjs to .js extensions
• Update bin entry for CLI verification script

Test plan

• Verify npm run build produces only ESM output
• Test importing the package in an ESM project
• Verify CLI command docusaurus-mcp-verify works correctly

🤖 Generated with Claude Code

[steve-calvert-glean]

Code review

Found 2 issues:

1. README documentation contains CommonJS examples that will break after ESM-only switch

The README.md contains require() examples for Vercel and Netlify adapters that will fail with "require() of ES Module not supported" after this change adds "type": "module" and removes CJS build output.

docusaurus-plugin-mcp-server/README.md

Lines 46 to 55 in 7ff27b0

	const { createVercelHandler } = require('docusaurus-plugin-mcp-server/adapters');
	const path = require('path');
	module.exports = createVercelHandler({
	docsPath: path.join(__dirname, '../build/mcp/docs.json'),
	indexPath: path.join(__dirname, '../build/mcp/search-index.json'),
	name: 'my-docs',
	baseUrl: 'https://docs.example.com',
	});
	```

2. Generated adapter files output CommonJS code that will cause runtime failures

The src/adapters/generator.ts generates adapter templates using require() and module.exports for Vercel/Netlify deployments. After this ESM-only switch, users running the generator will get non-functional code that fails at runtime.

docusaurus-plugin-mcp-server/src/adapters/generator.ts

Lines 56 to 68 in 7ff27b0

	const { createVercelHandler } = require('docusaurus-plugin-mcp-server/adapters');
	const path = require('path');
	const projectRoot = path.join(__dirname, '..');
	module.exports = createVercelHandler({
	docsPath: path.join(projectRoot, 'build/mcp/docs.json'),
	indexPath: path.join(projectRoot, 'build/mcp/search-index.json'),
	name: '${name}',
	version: '1.0.0',
	baseUrl: '${baseUrl}',
	});

Both issues require updating to ESM syntax (import/export default) to match the new module format.

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🤖 Generated with Claude Code

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