MCP: user-configured api.githubcopilot.com/mcp/ server loses the injected Copilot token on 1.0.81-10, and /mcp auth cannot rescue it (github.com advertises no dynamic client registration)

MCP: user-configured api.githubcopilot.com/mcp/ server loses the injected Copilot token on 1.0.81-10, and /mcp auth cannot rescue it (github.com advertises no dynamic client registration) #7365