Step 7.2: HLS client fetches live segments (log only)

- main/hls: task active while source.mode is hls/auto and hls_url is
  set. esp_http_client over HTTPS (IDF certificate bundle), redirects
  followed (max 5), streamed reads in 4 KB chunks to a sink callback.
- Master playlist: highest BANDWIDTH variant; URL resolution for
  absolute, host-relative and path-relative references; CRLF tolerant.
- Media playlist: TARGETDURATION, MEDIA-SEQUENCE, segments; start 3
  segments behind the live edge, fetch each new one in order, skip ahead
  if the window moved past us, reload after target/2 when nothing is new.
- Verified with Triple J Hottest (ABC, Akamai): 252 kbit/s AAC-LC
  variant chosen, 3 back-fill segments then one new ~10 s segment at a
  time, ~303 KB in ~1.25 s each; heap 439 KB, PSRAM 31.9 MB free.

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

main/CMakeLists.txt

@@ -1,5 +1,5 @@
-idf_component_register(SRCS "main.c" "project_cfg.c" "player.c" "audio_ring.c"
+idf_component_register(SRCS "main.c" "project_cfg.c" "player.c" "audio_ring.c" "hls.c"
                        INCLUDE_DIRS "."
-                       REQUIRES esp_app_format esp_hw_support heap
+                       REQUIRES esp_app_format esp_hw_support heap esp_http_client mbedtls esp_timer
                                 aes67_board aes67_health aes67_net aes67_ota aes67_ptp aes67_sdp_sap
                                 aes67_syslog aes67_tx aes67_web)