fix: don't leak escalated scopes in PRM for step-up test#154
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The scope-step-up scenario sets
scopesSupported: escalatedScopesin the PRM, which leaks the escalated scope (mcp:write) via discovery. This lets clients pass the test by just re-authenticating and picking upscopes_supportedfrom the PRM — without actually handling the 403insufficient_scoperesponse.Fix: set
scopesSupported: [initialScope]so onlymcp:basicis advertised in the PRM. The escalated scope (mcp:basic mcp:write) is only available from the 403 WWW-Authenticate header ontools/call.