Update and modernize build structure

[Strokkur424]

Changes:

• Update Gradle to latest (9.4.1).
• Move common subprojects root configuration into convention plugin common.gradle.kts.
• Replace dependency strings with Gradle version catalog.
• Move common modded configuration into convention plugin modded.gradle.kts.
• Mainstream archive name declaration (use archiveBaseName/archiveAppendix on an abstract task type level to avoid overriding the archiveFileName in every project.)
• Configure configuration cache and various other Gradle properties for improved performance.
• Cleans up .gitignore and adds .editorconfig and .gitattributes files