Fix tools visibility - revert to v0.1.6 authentication approach

- Disable issuer validation in BearerAuthProvider (issuer=None)
- Simplify authentication condition (remove auth_enabled check)
- Revert CORS middleware to simple configuration
- Fix OAuth metadata endpoint to match v0.1.6
- Apply conditional auth only to MCP server creation

Critical fixes for Claude AI tools discovery

saidsurucu-yargi-mcp-f5fa007/LICENSE

@@ -0,0 +1,21 @@
+MIT License
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