The provider Playground (LlmChatCard) only added the providerId/ prefix to models without a slash, so vendor-namespaced ids (moonshotai/kimi-k2.6, nvidia/zyphra/...) were sent bare and rejected with 'Ambiguous model' when the same id exists under multiple providers. Extracted qualifyPlaygroundModel() which always prefixes with the provider unless already qualified. Bug 1 ('unhashable type: dict') is an upstream NVIDIA NIM server error, not OmniRoute. Tests: 4 cases for the qualifier.
