chore(release): 2.1.0

Minor release adding the ClaudeCodeProvider for Claude Pro/Max
subscription users (PR #10) along with a rewritten README (PR #10)
and a repaired test suite (PR #11).

New public exports:
- ClaudeCodeProvider, ClaudeCodeConfig
- createClaudeCodeProvider
- 'claude-code' added to PROVIDER_REGISTRY and SUPPORTED_PROVIDERS

No breaking changes.

package.json

@@ -1,6 +1,6 @@
 {
   "name": "simple-ai-provider",
-  "version": "2.0.1",
+  "version": "2.1.0",
   "description": "A simple and extensible AI provider package for easy integration of multiple AI services",
   "main": "dist/index.js",
   "module": "dist/index.mjs",