icey 2.4.9

Fixed

• wrtc::codec_registry::hasEncoder now does a runtime probe (avcodec_alloc_context3 + avcodec_open2), with results cached. The prior implementation only checked avcodec_find_encoder_by_name, which on Linux distros that ship libavcodec with hardware-encoder wrappers built in (h264_nvenc, h264_vaapi, h264_qsv) returned true even when the runtime resources for those encoders (CUDA, VA-API drivers, etc.) were absent. The h264-on-macOS / videotoolbox path was unaffected; the fix prevents codec selection from picking a hardware encoder that exists at link time but cannot be opened at runtime, which surfaced as "Cannot open the video codec: Operation not permitted" in the icey-cli browser smoke on Linux CI.