fix: add manual META-INF/services files for NmsProvider ServiceLoader registration

The @autoservice KSP processor may not always generate the service file
correctly (e.g. due to paperweight dev bundle resolution issues). Adding
manual service files ensures V1_21_11NmsProvider and V26_1NmsProvider
are always discoverable by ServiceLoader at runtime.

Also makes ServiceLoader iteration robust against class loading failures
and updates the NMS template generator to auto-generate service files.

Agent-Logs-Url: https://github.com/SLNE-Development/surf-api/sessions/1c421ac7-9194-4697-91fd-1373913d3900

Co-authored-by: TheBjoRedCraft <143264463+TheBjoRedCraft@users.noreply.github.com>

Author: Copilot

surf-api-generator/src/main/kotlin/dev/slne/surf/api/gen/nms/NmsTemplateGenerator.kt

@@ -74,10 +74,35 @@ class NmsTemplateGenerator(
             generated++
         }
 
+        // Generate META-INF/services file for ServiceLoader registration
+        generateServiceFile(repoRoot, target)
+
         println("Generated $generated files for ${target.versionId} in ${targetSourceRoot.toAbsolutePath()}")
         return generated
     }
 
+    /**
+     * Generates the META-INF/services file for ServiceLoader registration.
+     * This ensures the NmsProvider implementation is discoverable at runtime,
+     * regardless of whether KSP annotation processing runs successfully.
+     */
+    private fun generateServiceFile(repoRoot: Path, target: NmsVersionConfig) {
+        val serviceDir = repoRoot.resolve(target.sourceModulePath)
+            .resolve("src/main/resources/META-INF/services")
+        serviceDir.createDirectories()
+
+        // Derive the provider class name from the reference module's NmsProvider
+        val referenceProviderPackage = "dev.slne.surf.api.paper.server.nms.$referenceVersionId"
+        val referenceProviderClass = "${referenceClassPrefix}NmsProvider"
+        val targetProviderPackage = "dev.slne.surf.api.paper.server.nms.${target.versionId}"
+        val targetProviderClass = "${target.classPrefix}NmsProvider"
+
+        val serviceFile = serviceDir.resolve("dev.slne.surf.api.paper.nms.common.NmsProvider")
+        serviceFile.writeText("$targetProviderPackage.$targetProviderClass\n")
+
+        println("Generated service file for ${target.versionId}: $targetProviderPackage.$targetProviderClass")
+    }
+
     /**
      * Transforms a relative path from the reference module to the target module.
      * Replaces the reference package directory segments with target ones.

surf-api-paper/surf-api-paper-nms/surf-api-paper-nms-common/src/main/kotlin/dev/slne/surf/api/paper/nms/common/NmsProvider.kt

@@ -98,13 +98,29 @@ interface NmsProvider {
          */
         val current: NmsProvider by lazy {
             val version = NmsVersion.current
-            val providers = java.util.ServiceLoader.load(
+            val serviceLoader = java.util.ServiceLoader.load(
                 NmsProvider::class.java,
                 NmsProvider::class.java.classLoader
-            ).toList()
+            )
+
+            // Iterate safely — skip providers whose classes can't be loaded
+            // (e.g. version-specific NMS classes not present on this server)
+            val providers = buildList {
+                val iterator = serviceLoader.iterator()
+                while (iterator.hasNext()) {
+                    try {
+                        add(iterator.next())
+                    } catch (e: java.util.ServiceConfigurationError) {
+                        log.atWarning().withCause(e).log("Skipping NmsProvider that failed to load")
+                    }
+                }
+            }
 
             log.atInfo().log("Looking for NmsProvider with version: %s", version)
-            log.atInfo().log("Available NmsProviders: %s", providers.map { "${it.version.name} (${it.version.versionPrefix})" }.joinToString(", "))
+            log.atInfo().log(
+                "Available NmsProviders: %s",
+                providers.joinToString(", ") { "${it.version.name} (${it.version.versionPrefix})" }
+            )
 
             val matched = providers.firstOrNull { it.version == version }
             if (matched != null) {
@@ -113,7 +129,10 @@ interface NmsProvider {
             } else {
                 log.atWarning().log("No exact match for NmsProvider version %s, using fallback", version)
                 val fallback = providers.maxByOrNull { it.version.versionPrefix }
-                    ?: error("No NmsProvider implementations found")
+                    ?: error(
+                        "No NmsProvider implementations found for version $version. " +
+                                "Ensure the correct NMS module is included in the classpath."
+                    )
                 log.atWarning().log("Selected fallback NmsProvider: %s", fallback.version.name)
                 fallback
             }

surf-api-paper/surf-api-paper-nms/surf-api-paper-nms-v1-21-11/src/main/resources/META-INF/services/dev.slne.surf.api.paper.nms.common.NmsProvider

@@ -0,0 +1 @@
+dev.slne.surf.api.paper.server.nms.v1_21_11.V1_21_11NmsProvider

surf-api-paper/surf-api-paper-nms/surf-api-paper-nms-v26-1/src/main/resources/META-INF/services/dev.slne.surf.api.paper.nms.common.NmsProvider

@@ -0,0 +1 @@
+dev.slne.surf.api.paper.server.nms.v26_1.V26_1NmsProvider