feat: add core and extensions suites for SDK tiering (#117)

* feat: add core and extensions suites for SDK tiering

Add new suites to support SDK tiering requirements:

Client suites:
- core (19 scenarios): Tier 1 requirements (base + auth)
- extensions (2 scenarios): Optional protocol extensions (client credentials)
- all (21 scenarios): Everything (core + extensions)
- auth (15 scenarios): Auth scenarios only (excludes extensions)

Server suites:
- core: Alias for 'active' (tier 1 requirements)

This allows SDK developers to run --suite core for tier 1 certification
while keeping extension tests available but not blocking.

* feat: promote elicitation tests from pending to active

Move 3 elicitation scenarios to active suite:
- elicitation-sep1330-enums
- tools-call-elicitation
- elicitation-sep1034-defaults

These tests are now passing in the Python SDK and ready for
SDK tiering requirements.

Remaining pending tests (2):
- json-schema-2020-12 (blocked on SDK PR #1135)
- server-sse-polling (blocked on SDK PR #1129)

src/scenarios/client/auth/index.ts

@@ -22,6 +22,7 @@ import {
   ClientCredentialsBasicScenario
 } from './client-credentials';
 
+// Auth scenarios (required for tier 1)
 export const authScenariosList: Scenario[] = [
   ...metadataScenarios,
   new AuthBasicCIMDScenario(),
@@ -34,7 +35,11 @@ export const authScenariosList: Scenario[] = [
   new ScopeRetryLimitScenario(),
   new ClientSecretBasicAuthScenario(),
   new ClientSecretPostAuthScenario(),
-  new PublicClientAuthScenario(),
+  new PublicClientAuthScenario()
+];
+
+// Extension scenarios (optional for tier 1 - protocol extensions)
+export const extensionScenariosList: Scenario[] = [
   new ClientCredentialsJwtScenario(),
   new ClientCredentialsBasicScenario()
 ];