chore(changes): condense and split pending changelog fragments

- Shorten the Hachidori backend fragment to its user-visible outcomes
- Move the fork submodule note into an internal fragment
- Split stats dashboard history-line mining into its own fixed fragment
- Reclassify the setup launcher label fragment as internal
- Drop the Electron/undici security fragment

changes/stats-mining-history-line.md

@@ -0,0 +1,4 @@
+type: fixed
+area: stats
+
+- Cards mined from the stats dashboard keep the selected history line and media instead of being rebuilt from the current mpv subtitle. Stats cards carry a `SubMiner::Stats` tag so polling mode preserves their context too.