Rename package to cy.hexor.furumi, add F-Droid compatibility

- Rename applicationId and all sources from com.example.furumi_android to cy.hexor.furumi
- Add WTFPL LICENSE
- Add fastlane metadata
- Add fdroiddata build metadata cy.hexor.furumi.yml
- Remove foojay-resolver plugin (blocked by F-Droid scanner)

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

settings.gradle.kts

@@ -11,9 +11,6 @@ pluginManagement {
         gradlePluginPortal()
     }
 }
-plugins {
-    id("org.gradle.toolchains.foojay-resolver-convention") version "1.0.0"
-}
 dependencyResolutionManagement {
     repositoriesMode.set(RepositoriesMode.FAIL_ON_PROJECT_REPOS)
     repositories {