Add missing mixins to Forge

Add issues url to the mod
Add water hunting to avians

buildSrc/src/main/kotlin/build-extensions.kt

@@ -29,6 +29,9 @@ value class ModData(private val project: Project) {
 	val description: String get() = modProp("description")
 	val license: String get() = modProp("license")
 	val credits: String get() = modProp("credits")
+	val issueUrl: String get() = modPropOrNull("issue_url") ?: ""
+	val homepageUrl: String get() = modPropOrNull("homepage_url") ?: ""
+	val sourcesUrl: String get() = modPropOrNull("sources_url") ?: ""
 	val minecraft_version: String get() = propOrNull("minecraft_version") ?: project.stonecutterBuild.current.version
 
 	fun propOrNull(key: String) = project.prop(key)

buildSrc/src/main/kotlin/multiloader-common.gradle.kts

@@ -57,6 +57,9 @@ tasks {
 			"license" to commonMod.license,
 			"description" to commonMod.description,
 			"credits" to commonMod.credits,
+			"issue_url" to commonMod.issueUrl,
+			"homepage_url" to commonMod.homepageUrl,
+			"sources_url" to commonMod.sourcesUrl,
 			"minecraft_version" to commonMod.propOrNull("minecraft_version"),
 			"minecraft_version_range" to commonMod.propOrNull("minecraft_version_range"),
 			"fabric_api_version" to commonMod.propOrNull("fabric_api_version"),