(refac) Move language-processing into functions

It's long surpassed the single-responsibility library it once was, and is as such out of place in its original location, and fits better among the function-type modules.

code/functions/language-processing/java/nu/marginalia/language/config/LanguageConfigLocation.java

@@ -0,0 +1,43 @@
+package nu.marginalia.language.config;
+
+import nu.marginalia.WmsaHome;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.StandardOpenOption;
+
+sealed public interface LanguageConfigLocation {
+    InputStream findLanguageConfiguration() throws IOException;
+
+    final class Auto implements LanguageConfigLocation {
+        @Override
+        public InputStream findLanguageConfiguration() throws IOException {
+            Path filesystemPath = WmsaHome.getLangugeConfig();
+            if (Files.exists(filesystemPath)) {
+                return Files.newInputStream(filesystemPath, StandardOpenOption.READ);
+            }
+            if (Boolean.getBoolean("language.experimental")) {
+                return ClassLoader.getSystemResourceAsStream("languages-experimental.xml");
+            } else {
+                return ClassLoader.getSystemResourceAsStream("languages-default.xml");
+            }
+        }
+    }
+
+    final class Experimental implements LanguageConfigLocation {
+        @Override
+        public InputStream findLanguageConfiguration() throws IOException {
+            return ClassLoader.getSystemResourceAsStream("languages-experimental.xml");
+        }
+    }
+
+    final class Default implements LanguageConfigLocation {
+
+        @Override
+        public InputStream findLanguageConfiguration() throws IOException {
+            return ClassLoader.getSystemResourceAsStream("languages-default.xml");
+        }
+    }
+}