fix: add diagnostic logging to createPlotSafe failure paths

Log plot coordinates, area, and attempted owner UUID for all three failure modes: INSERT no-op (plot exists), missing generated key, and SQLException in sendBatch.

Author: ByteExceptionM

Core/src/main/java/com/plotsquared/core/database/SQLManager.java

@@ -425,8 +425,9 @@ public synchronized boolean sendBatch() {
                 Iterator<Entry<Plot, Queue<UniqueStatement>>> iterator =
                         this.plotTasks.entrySet().iterator();
                 while (iterator.hasNext()) {
+                    Entry<Plot, Queue<UniqueStatement>> entry = null;
                     try {
-                        Entry<Plot, Queue<UniqueStatement>> entry = iterator.next();
+                        entry = iterator.next();
                         Queue<UniqueStatement> tasks = entry.getValue();
                         if (tasks.isEmpty()) {
                             iterator.remove();
@@ -458,6 +459,9 @@ public synchronized boolean sendBatch() {
                         LOGGER.error("============ DATABASE ERROR ============");
                         LOGGER.error("There was an error updating the database.");
                         LOGGER.error(" - It will be corrected on shutdown");
+                        LOGGER.error(" - Task: {}, Plot: {}",
+                                task != null ? task.method : "null",
+                                entry != null ? entry.getKey().getId().toCommaSeparatedString() : "unknown");
                         LOGGER.error("========================================");
                         e.printStackTrace();
                         LOGGER.error("========================================");
@@ -1097,7 +1101,12 @@ public void execute(PreparedStatement statement) {
 
             @Override
             public void addBatch(PreparedStatement statement) throws SQLException {
-                if (statement.execute() || statement.getUpdateCount() > 0) {
+                int updateCount = 0;
+                boolean hasResultSet = statement.execute();
+                if (!hasResultSet) {
+                    updateCount = statement.getUpdateCount();
+                }
+                if (hasResultSet || updateCount > 0) {
                     try (ResultSet keys = supportsGetGeneratedKeys ? statement.getGeneratedKeys() : statement.getResultSet()) {
                         if (keys.next()) {
                             plot.temp = keys.getInt(1);
@@ -1121,7 +1130,21 @@ public PreparedStatement get() throws SQLException {
                             }
                             return;
                         }
+                        LOGGER.warn(
+                                "createPlotSafe: INSERT succeeded (updateCount={}) but no generated key returned for plot {} in area {} (attempted owner: {})",
+                                updateCount,
+                                plot.getId().toCommaSeparatedString(),
+                                plot.getArea(),
+                                plot.getOwnerAbs()
+                        );
                     }
+                } else {
+                    LOGGER.warn(
+                            "createPlotSafe: plot {} in area {} already exists in database, INSERT was no-op (attempted owner: {})",
+                            plot.getId().toCommaSeparatedString(),
+                            plot.getArea(),
+                            plot.getOwnerAbs()
+                    );
                 }
                 if (failure != null) {
                     failure.run();