Root cause: certificate_versions.csr_pem is nullable in the schema but
Go code scanned it into a plain string. Used sql.NullString in
ListVersions and GetLatestVersion to handle NULL values correctly.
Also includes: partial update fetch-merge-update pattern to prevent FK
violations, nil directory guard in discovery service, diagnostic slog
logging in handlers, export handler 422 for unparseable PEM, OpenAPI
spec corrections, MCP tool description improvements, and test fixes.
Rewrites the Release Sign-Off section in testing-guide.md to individual
test-level granularity (320 rows) with smoke test results audited and
checked off (121 pass, 5 skip, 194 manual remaining).
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Separate standalone binary (cmd/mcp-server/) using official MCP Go SDK
(modelcontextprotocol/go-sdk v1.4.1) with stdio transport. Stateless HTTP
proxy translates MCP tool calls to certctl REST API requests. 76 tools
across 16 resource domains with typed input structs and jsonschema tags
for automatic LLM-friendly schema generation.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
shankar0123