fix: improve threaded world compatibility and chunk reads in 1.1.15

Add regression tests and per-dimension progress diagnostics. Document the unresolved C2ME random-initialization redirect conflict.

tests/PauseOwnershipRegression.java

@@ -0,0 +1,16 @@
+import dev.modzuozhi.core.compat.PauseOwnership;
+
+public final class PauseOwnershipRegression {
+    public static void main(String[] args) {
+        for (int mask = 0; mask < 16; mask++) {
+            boolean paused = PauseOwnership.shouldPause((mask & 1) != 0, (mask & 2) != 0,
+                    (mask & 4) != 0, (mask & 8) != 0);
+            if (paused != (mask == 15)) throw new AssertionError("Loading screen paused worker: " + mask);
+        }
+        if (PauseOwnership.workerOwns(false, false, false)) throw new AssertionError("Startup routed to absent worker");
+        if (!PauseOwnership.workerOwns(true, false, false)) throw new AssertionError("Running loop lost ownership");
+        if (!PauseOwnership.workerOwns(true, true, true)) throw new AssertionError("In-flight tick lost ownership");
+        if (PauseOwnership.workerOwns(true, true, false)) throw new AssertionError("Idle paused worker kept requests");
+        System.out.println("PASS: loading/login pause gate and drained-pause chunk ownership");
+    }
+}