chore(release): 0.7.0

Version bumped across package.json, tauri.conf.json and Cargo.toml (+ lock),
CHANGELOG entry written from the five commits in the range rather than from the
trace extractor's output — VideoPlayer.svelte alone carries dozens of TRACES, so
the generated draft named most of the app's requirements for a five-commit
release.

DR-188 is retargeted: it recorded the native-video default as waiting on the
background-audio handoff, which is now fixed (DR-196), so it records the
completed flip and the evidence for it instead.

Minor, not patch: the rendering path changes underneath every Android user.

src-tauri/tauri.conf.json

@@ -1,7 +1,7 @@
 {
   "$schema": "https://schema.tauri.app/config/2",
   "productName": "jellytau",
-  "version": "0.6.0",
+  "version": "0.7.0",
   "identifier": "com.dtourolle.jellytau",
   "build": {
     "beforeDevCommand": "bun run dev",