Step 7.3: decode HLS TS segments to PCM (own TS demux + AAC decoder)

- main/decoder: MPEG-TS demux (packets reassembled across HTTP chunks,
  PAT -> PMT -> first ADTS-AAC PID, PES headers stripped) feeding the
  esp_audio_codec simple AAC decoder (ADTS, AAC-Plus enabled for HE-AAC
  v1/v2 variants). 7.3 only counts and logs PCM per segment.
- esp_audio_codec pinned to ~2.5.0: 2.6+ needs P4 rev >= 3 (this board
  is rev 1.3). Noted in CLAUDE.md, also for esp_audio_effects < 1.4.
- The library's combined TS decoder lost ~8% of the frames (segments
  decoded to 7.9-9.6 s, "decode error -1"); with the own demux every
  segment is sample exact: 441344 / 440320 frames = 10.008 / 9.985 s,
  matching EXTINF 10.0078 / 9.9846 (431 / 430 AAC frames), no errors.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

main/player.c

@@ -7,6 +7,7 @@
 #include "aes67_tx.h"
 #include "aes67_web.h"
 #include "audio_ring.h"
+#include "decoder.h"
 #include "hls.h"
 #include "esp_log.h"
 #include "freertos/FreeRTOS.h"
@@ -113,7 +114,11 @@ esp_err_t player_init(void)
     player_apply(src);
     cJSON_Delete(src);
     xTaskCreate(test_producer, "test_prod", 3072, NULL, 5, NULL);
-    err = hls_start(NULL);  // 7.2: fetch and log only; decoding in 7.3
+    err = decoder_init();
+    if (err != ESP_OK) {
+        return err;
+    }
+    err = hls_start(decoder_feed);  // 7.3: decode and log; resampling + ring in 7.4
     if (err != ESP_OK) {
         return err;
     }