Release v0.3.8

Marketplace validation release for LobeHub and other MCP catalogs. No Portkey Admin API surface changes.

Added

• Register a built-in plan_portkey_admin_workflow MCP prompt so clients and catalogs can discover an invokable prompt; the prompt validates argument lengths, embeds the workflow guide as an MCP resource, and reminds clients to treat user task text as lower-priority context.
• Register a static portkey-admin://docs/workflow-guide MCP resource with safe usage guidance and assistant-priority annotations for discovery-first Portkey Admin workflows.
• Add MCP e2e coverage for prompt/resource capabilities, listing, prompt rendering, resource reading, and no-key catalog inspection.

Changed

• Allow the shared MCP service factory to initialize without PORTKEY_API_KEY so marketplaces can inspect server capabilities before users provide secrets. Direct PortkeyService construction and actual Admin API calls still require real credentials.
• GitHub Releases now use the matching CHANGELOG.md version section as the release body (with the auto-generated PR list appended), instead of auto-generated notes alone.

Fixed

• Use LobeHub's lowercase codeswhat-portkey-admin-mcp badge slug so owner-claim scans match the marketplace page exactly.

What's Changed

• 🔧 config(release): use CHANGELOG section as GitHub Release notes by @scttbnsn in #14

Full Changelog: v0.3.7...v0.3.8