The sep-2243 scenario check IDs drifted from the requirement-traceability
yaml in #259 — the code emitted one ID per test case while the yaml
declares one per normative requirement, so the IDs no longer matched.
Rename the emitted IDs so a check ID maps to a single MUST/SHOULD and is
emitted once per case (the per-case detail moves to name/description),
matching the repo's existing 'same id, vary status/message' convention:
- mcp-method-header-* / mcp-name-header-* -> client-includes-standard-headers
- reject-invalid-tool-* / keep-valid-tool -> client-reject-invalid-tool
- server-accepts-{lower,upper}case-name -> header-name-case-insensitive
- server reject status checks (mismatch/missing/case x method/name)
-> server-reject-invalid-headers
- their error-code variants -> server-reject-error-code
Merge the yaml's server-reject-mismatch + server-reject-status into one
server-reject-invalid-headers MUST (HTTP 400 on a header-validation
failure); keep server-reject-error-code as the SHOULD. Base64/custom-header
rejection checks keep their own param-validation IDs (out of scope here).
Gates and the whitespace-acceptance check keep their scenario-matching
names. No behavior change — only check IDs, descriptions, and the yaml.
70f7ba0004