DeadAir plays an HLS playlist of the original, with a pause of your own (#181, #182)

DeadAir made a shortened copy of each episode with ffmpeg: as much disk
again as the original, one pause length for everyone, and a minutes-long
wait after the download. Seeking past silences instead was tried on an
iPhone and left about 1.3 s of nothing at every cut (#178).

Now it finds a file's silences once (silencedetect, plus ffprobe for
each frame's byte position) and stores a plan for each pause a person
can choose, 0.2 to 0.5 s: the cuts, and the frames kept as byte ranges
of the original. /media/{id}/deadair.m3u8 hands this person's plan out
as an HLS playlist of ranges of /media/{id}/deadair.mp3, the original.
Tested on iOS Safari first (#180): no gap at the cuts, plays locked,
seeks exactly, and needs no ID3 timestamp in front of each piece.

Other browsers get hls.js (1.6.19, the light build), loaded only when
needed. Not where canPlayType says it can play HLS: Chromium answers
"maybe" and then fails on MP3 ranges with "stream parsing failed", so
only Apple's browsers play the playlist themselves.

The pause is per person and per show, on deadair_prefs.pause_ms, 0.3 s
unless chosen; 0.2 s, what the copies left, made speech sound rushed.
AAC in MP4 has no ranges a playlist can use, so only MP3 and ADTS AAC
are shortened (the library is 803 MP3s and no .m4a). The copies, their
table and #179's expiry go: the first start drops the table and deletes
the files it names, only those named name.deadair.*.

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

package-lock.json

@@ -7,7 +7,8 @@
       "name": "ipx-web",
       "dependencies": {
         "@swc/core": "^1.16.2",
-        "@swc/html": "^1.16.2"
+        "@swc/html": "^1.16.2",
+        "hls.js": "1.6.19"
       },
       "devDependencies": {
         "@playwright/test": "^1.56.0",
@@ -871,6 +872,12 @@
         "node": ">=16.20.0"
       }
     },
+    "node_modules/hls.js": {
+      "version": "1.6.19",
+      "resolved": "https://registry.npmjs.org/hls.js/-/hls.js-1.6.19.tgz",
+      "integrity": "sha512-A//aZeaAgM5rgUCbTURD4gkfyw5Uag2/4Jky7CfDOukL/DN+P5DjbgK2BYteyP3/KnCkPfkGVkbLxQG2T0AbUQ==",
+      "license": "Apache-2.0"
+    },
     "node_modules/playwright": {
       "version": "1.63.0",
       "resolved": "https://registry.npmjs.org/playwright/-/playwright-1.63.0.tgz",