chore: reorganize dist/, remove release/, update install paths

- Move all distribution binaries to dist/ (Linux .deb + Windows .exe)
- Remove release/ directory (redundant, merged into dist/)
- Remove root-level .deb and .tar.gz leftovers
- Update install.sh to reference dist/ instead of release/
- Update README.md with correct dist/ paths and .deb-first Linux install
- Update .gitignore: ignore root binaries, keep dist/*.deb and dist/*.exe

.gitignore

@@ -44,4 +44,10 @@ app.*.map.json
 /android/app/profile
 /android/app/release
 
-
+# Distribution binaries — only keep under dist/
+*.deb
+*.tar.gz
+*.exe
+!dist/*.deb
+!dist/*.exe
+release/