feat: add DockerRuntimeOrchestrator with docker-java

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/test/java/net/siegeln/cameleer/saas/runtime/DockerRuntimeOrchestratorTest.java

@@ -0,0 +1,32 @@
+package net.siegeln.cameleer.saas.runtime;
+
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.*;
+
+class DockerRuntimeOrchestratorTest {
+
+    @Test
+    void runtimeConfig_parseMemoryLimitBytes_megabytes() {
+        assertEquals(512 * 1024 * 1024L, parseMemoryLimit("512m"));
+    }
+
+    @Test
+    void runtimeConfig_parseMemoryLimitBytes_gigabytes() {
+        assertEquals(1024L * 1024 * 1024, parseMemoryLimit("1g"));
+    }
+
+    @Test
+    void runtimeConfig_parseMemoryLimitBytes_bytes() {
+        assertEquals(536870912L, parseMemoryLimit("536870912"));
+    }
+
+    private long parseMemoryLimit(String limit) {
+        var l = limit.trim().toLowerCase();
+        if (l.endsWith("g")) {
+            return Long.parseLong(l.substring(0, l.length() - 1)) * 1024 * 1024 * 1024;
+        } else if (l.endsWith("m")) {
+            return Long.parseLong(l.substring(0, l.length() - 1)) * 1024 * 1024;
+        }
+        return Long.parseLong(l);
+    }
+}