Port optional integrations and finish Age creation and modifier lifecycle

ports/mc263/build.gradle

@@ -3,6 +3,39 @@ plugins {
     id 'net.neoforged.moddev' version '2.0.148'
 }
 
+repositories {
+    maven { url = 'https://www.cursemaven.com'; content { includeGroup 'curse.maven' } }
+    maven { url = 'https://api.modrinth.com/maven'; content { includeGroup 'maven.modrinth' } }
+    maven {
+        name = 'TerraBlenderMaven'
+        url = 'https://maven.minecraftforge.net/releases/'
+        content { includeGroup 'com.github.glitchfiend' }
+    }
+    maven {
+        name = 'JaredsMaven'
+        url = 'https://maven.blamejared.com'
+        content { includeGroup 'mezz.jei'; includeGroup 'net.mezzdev.config' }
+    }
+}
+dependencies {
+    // Compile against the 26.3 baseline API; a local current Ruins JAR can override it.
+    def ruinsDependency = project.hasProperty('ruinsJar') ? files(project.property('ruinsJar'))
+            : 'curse.maven:ruins-227873:8962119'
+    compileOnly ruinsDependency
+    if (project.hasProperty('withRuins')) localRuntime ruinsDependency
+    compileOnly "maven.modrinth:e0bNACJD:${serene_seasons_version_id}"
+    compileOnly "maven.modrinth:s3dmwKy5:${glitchcore_version_id}"
+    if (project.hasProperty('withSereneSeasons')) {
+        localRuntime "maven.modrinth:e0bNACJD:${serene_seasons_version_id}"
+        localRuntime "maven.modrinth:s3dmwKy5:${glitchcore_version_id}"
+    }
+    compileOnly "com.github.glitchfiend:TerraBlender-neoforge:${minecraft_version}-${terrablender_version}"
+    if (project.hasProperty('withTerraBlender')) localRuntime "com.github.glitchfiend:TerraBlender-neoforge:${minecraft_version}-${terrablender_version}"
+    // Plugin-only API dependency: JEI is never bundled or required at runtime.
+    compileOnly "mezz.jei:jei-${minecraft_version}-neoforge-api:${jei_version}"
+    if (project.hasProperty('withJei')) localRuntime "mezz.jei:jei-${minecraft_version}-neoforge:${jei_version}"
+}
+
 group = 'net.dnorberg.rivencraft'
 version = mod_version