Add gzip-aware crash upload and OTA staging build/deploy tooling.

This restores the interrupted stash work on a dedicated feature branch, including backend decoding support, Dockerized build scripts, and staging channel artifacts for end-to-end OTA validation.

Co-authored-by: Cursor <cursoragent@cursor.com>

scripts/generate-ota-v0.sh

@@ -4,9 +4,12 @@
 # Usage:
 #   ./scripts/generate-ota-v0.sh path/to/app-release.apk https://host[:port] [out-dir] [channel]
 #
+#   channel — JSON file under v0/ota/channel/ (default: stable). Use staging for QA.
+#   RELEASE_NOTES — optional env, embedded in manifest.
+#
 #   channel — JSON under v0/ota/channel/ (stable, staging, dev, nightly, or custom)
 # Writes under out-dir (default: ./ota-publish):
-#   v0/ota/channel/stable.json
+#   v0/ota/channel/<channel>.json
 #   v0/ota/00/00.MM/00.MM.mm/android_cast_00.MM.mm.BB_manifest.json
 #   v0/ota/00/00.MM/00.MM.mm/android_cast_00.MM.mm.BB_sign.json
 #   v0/ota/00/00.MM/00.MM.mm/android_cast_00.MM.mm.BB.otapkg
@@ -17,6 +20,19 @@ apk="${1:?APK path required}"
 host_base="${2:?Base URL required, e.g. https://192.168.1.1:8080}"
 out_dir="${3:-ota-publish}"
 channel="${4:-stable}"
+release_notes="${RELEASE_NOTES:-}"
+json_notes() {
+  if command -v jq >/dev/null 2>&1; then
+    jq -n --arg n "$release_notes" '$n'
+  else
+    local esc="${release_notes//\\/\\\\}"
+    esc="${esc//\"/\\\"}"
+    esc="${esc//$'\n'/\\n}"
+    esc="${esc//$'\r'/}"
+    printf '"%s"' "$esc"
+  fi
+}
+NOTES_JSON="$(json_notes)"
 
 if [[ ! -f "$apk" ]]; then
   echo "APK not found: $apk" >&2
@@ -84,7 +100,7 @@ cat >"${rel_dir}/${manifest_name}" <<EOF
   "signUrl": "${sign_url}",
   "sizeBytes": ${apk_size},
   "mandatory": false,
-  "releaseNotes": ""
+  "releaseNotes": ${NOTES_JSON}
 }
 EOF
 
@@ -113,7 +129,7 @@ cat >"${rel_dir}/${manifest_name}" <<EOF
   "bundleSha256": "${bundle_sha256}",
   "bundleSizeBytes": ${bundle_size},
   "mandatory": false,
-  "releaseNotes": ""
+  "releaseNotes": ${NOTES_JSON}
 }
 EOF