docs(src): add examples alias and general cleanup (#2763)

src/cbs.h

@@ -1,6 +1,6 @@
 /**
  * @file src/cbs.h
- * @brief todo
+ * @brief Declarations for FFmpeg Coded Bitstream API.
  */
 #pragma once
 
@@ -31,7 +31,10 @@ namespace cbs {
   make_sps_h264(const AVCodecContext *ctx, const AVPacket *packet);
 
   /**
-   * Check if SPS->VUI is present
+   * @brief Validates the Sequence Parameter Set (SPS) of a given packet.
+   * @param packet The packet to validate.
+   * @param codec_id The ID of the codec used (either AV_CODEC_ID_H264 or AV_CODEC_ID_H265).
+   * @return True if the SPS->VUI is present in the active SPS of the packet, false otherwise.
    */
   bool
   validate_sps(const AVPacket *packet, int codec_id);