chore: clean up .gitignore — sort folders before files, add .idea/icon.svg exclusion

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: michaelbel

.gitignore

@@ -1,11 +1,11 @@
-/.github/keystore_release.jks
-/.github/keystore.properties
-.kotlin
+.claude
 .gradle
 .idea
-.claude
+!.idea/icon.svg
+.kotlin
 build
 build-cache
 generated
+/.github/keystore.properties
+/.github/keystore_release.jks
 local.properties
-releaseNotes.txt