Remove the eight explicit curve overrides so Go 1.27 honors tlsmlkem=0
across Server listeners, node links and outbound transports. Remove the
unused shared curve option and add wire-level regression coverage.
Document CA trust and TLS upgrade behavior, retain the investigation
artifacts, and exclude their synthetic routes from the rebrand guard.
The product compatibility baseline remains unchanged.
Validation: focused race tests, HTTP tests, lint, compatibility guard
positive/negative controls, and a fresh Linux build with three isolated
OIDC integration scenarios all pass.
Adversarial review: Claude Code Fable 5.1, max effort.
Final verdict: APPROVE FOR COMMIT.
Signed-off-by: Feng Ruohang <rh@vonng.com>