v1.2.0: Fix app icons and DockTilePlugin rename

- Rename WarpDockTilePlugin to GalaxyDockTilePlugin
- Fix runtime icon switching to load from compiled-in assets
- Add NSDockTilePlugIn key to embedded Info.plist
- Replace all channel icons with padded Galaxy variants
- Update build.rs references for renamed plugin
- No longer requires post-bundle steps for icon switching
- Bump version to 1.2.0

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

app/src/bin/oss.rs

@@ -62,6 +62,8 @@ embed_plist::embed_info_plist_bytes!(r#"
     <array><dict><key>CFBundleURLName</key><string>Galaxy</string><key>CFBundleURLSchemes</key><array><string>galaxyai</string></array></dict></array>
     <key>NSHumanReadableCopyright</key>
     <string>© 2026, Samsung Electronics Co., Ltd.</string>
+    <key>NSDockTilePlugIn</key>
+    <string>GalaxyDockTilePlugin.docktileplugin</string>
     </dict>
     </plist>
 "#.as_bytes());