unoserver docker (#6328)

# Description of Changes

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- What was changed
- Why the change was made
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## Checklist

### General

- [ ] I have read the [Contribution
Guidelines](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/CONTRIBUTING.md)
- [ ] I have read the [Stirling-PDF Developer
Guide](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/DeveloperGuide.md)
(if applicable)
- [ ] I have read the [How to add new languages to
Stirling-PDF](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/devGuide/HowToAddNewLanguage.md)
(if applicable)
- [ ] I have performed a self-review of my own code
- [ ] My changes generate no new warnings

### Documentation

- [ ] I have updated relevant docs on [Stirling-PDF's doc
repo](https://github.com/Stirling-Tools/Stirling-Tools.github.io/blob/main/docs/)
(if functionality has heavily changed)
- [ ] I have read the section [Add New Translation
Tags](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/devGuide/HowToAddNewLanguage.md#add-new-translation-tags)
(for new translation tags only)

### Translations (if applicable)

- [ ] I ran
[`scripts/counter_translation.py`](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/docs/counter_translation.md)

### UI Changes (if applicable)

- [ ] Screenshots or videos demonstrating the UI changes are attached
(e.g., as comments or direct attachments in the PR)

### Testing (if applicable)

- [ ] I have run `task check` to verify linters, typechecks, and tests
pass
- [ ] I have tested my changes locally. Refer to the [Testing
Guide](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/DeveloperGuide.md#7-testing)
for more details.

app/common/src/main/java/stirling/software/common/util/ProcessExecutor.java

@@ -15,6 +15,7 @@ import java.util.Set;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.Semaphore;
 import java.util.concurrent.TimeUnit;
+import java.util.concurrent.TimeoutException;
 
 import io.github.pixee.security.BoundedLineReader;
 
@@ -202,7 +203,15 @@ public class ProcessExecutor {
         boolean useSemaphore = true;
         List<String> commandToRun = command;
         if (shouldUseUnoServerPool(command)) {
-            unoLease = unoServerPool.acquireEndpoint();
+            try {
+                unoLease = unoServerPool.acquireEndpoint(timeoutDuration, TimeUnit.MINUTES);
+            } catch (TimeoutException e) {
+                throw new IOException(
+                        "All unoserver endpoints busy; request timed out after "
+                                + timeoutDuration
+                                + " minutes",
+                        e);
+            }
             commandToRun = applyUnoServerEndpoint(command, unoLease.getEndpoint());
             useSemaphore = false;
         }

app/common/src/main/java/stirling/software/common/util/UnoServerPool.java

@@ -3,8 +3,11 @@ package stirling.software.common.util;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
+import java.util.Locale;
 import java.util.concurrent.BlockingQueue;
 import java.util.concurrent.LinkedBlockingQueue;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.TimeoutException;
 import java.util.concurrent.atomic.AtomicBoolean;
 
 import stirling.software.common.model.ApplicationProperties;
@@ -42,6 +45,27 @@ public class UnoServerPool {
         return new UnoServerLease(endpoints.get(index), index, this);
     }
 
+    /** Fail-fast variant; non-positive timeout falls back to unbounded acquire. */
+    public UnoServerLease acquireEndpoint(long timeout, TimeUnit unit)
+            throws InterruptedException, TimeoutException {
+        if (endpoints.isEmpty()) {
+            return new UnoServerLease(defaultEndpoint(), null, this);
+        }
+        if (timeout <= 0) {
+            return acquireEndpoint();
+        }
+
+        Integer index = availableIndices.poll(timeout, unit);
+        if (index == null) {
+            throw new TimeoutException(
+                    "Timed out waiting for a free unoserver endpoint after "
+                            + timeout
+                            + " "
+                            + unit.name().toLowerCase(Locale.ROOT));
+        }
+        return new UnoServerLease(endpoints.get(index), index, this);
+    }
+
     private void releaseEndpoint(Integer index) {
         if (index != null) {
             availableIndices.offer(index);