Complete private authentication, server integrations and activity reporting

Add Fabric/Forge version builds and Paper integration, preserve permanent player identities across renames, harden session authorization, and surface privacy-conscious launcher/server activity in the panel.

integrations/paper/build.gradle

@@ -0,0 +1,17 @@
+repositories { maven { url = 'https://hub.spigotmc.org/nexus/content/repositories/snapshots/' } }
+dependencies {
+    implementation project(':common')
+    implementation 'com.google.code.gson:gson:2.10.1'
+    compileOnly 'org.spigotmc:spigot-api:1.20.1-R0.1-SNAPSHOT'
+}
+processResources {
+    inputs.property 'version', project.version
+    filesMatching('plugin.yml') { expand(version: project.version) }
+}
+jar {
+    archiveBaseName = 'scopenet-paper'
+    duplicatesStrategy = DuplicatesStrategy.EXCLUDE
+    from project(':common').sourceSets.main.output
+    from { configurations.runtimeClasspath.findAll { it.name.endsWith('.jar') && !it.name.startsWith('common-') }.collect { zipTree(it) } }
+    exclude 'META-INF/*.SF', 'META-INF/*.RSA', 'META-INF/*.DSA'
+}