Replace copyright after all third-party sources have been eliminated

.idea/copyright/libquassel.xml

build.gradle.kts

buildSrc/build.gradle.kts

...de/justjanne/coverageconverter/CoverageConverterAction.kt

...justjanne/coverageconverter/CoverageConverterExtension.kt

...de/justjanne/coverageconverter/CoverageConverterPlugin.kt

...lugins/de.justjanne.jacoco-cobertura-converter.properties

gradle/wrapper/gradle-wrapper.properties

libquassel-annotations/build.gradle.kts

libquassel-annotations/gradle.properties

...n/kotlin/de/justjanne/libquassel/annotations/Generated.kt

...otlin/de/justjanne/libquassel/annotations/ProtocolSide.kt

.../kotlin/de/justjanne/libquassel/annotations/SyncedCall.kt

.../kotlin/de/justjanne/libquassel/annotations/SyncedData.kt

...otlin/de/justjanne/libquassel/annotations/SyncedObject.kt

libquassel-client/build.gradle.kts

libquassel-client/gradle.properties

...ustjanne/libquassel/client/exceptions/IrcListException.kt

...lin/de/justjanne/libquassel/client/io/CoroutineChannel.kt

...stjanne/libquassel/client/io/FixedDeflaterOutputStream.kt