fix(coding-agent): used authenticated registry models by default

Required CLI model registries to expose getAvailable() and used that authenticated
set whenever callers omit availableModels. Deferred SDK and bench/dry-balance
resolution now lets configured roles beat unauthenticated catalog id collisions.

Updated resolver test registries and made the #6508 regression omit the explicit
availableModels option, covering the deferred-caller path from the review.

Fixes #6508

packages/coding-agent/src/cli/bench-cli.ts

@@ -76,6 +76,7 @@ export interface BenchCommandArgs {
 
 export interface BenchModelRegistry {
 	getAll(): Model<Api>[];
+	getAvailable(): Model<Api>[];
 	getApiKey(model: Model<Api>, sessionId?: string): Promise<string | undefined>;
 	resolver(model: ApiKeyResolverModel, sessionId?: string): ApiKeyResolver;
 	hasConfiguredAuth?(model: Model<Api>): boolean;