[api-minor] Add intent support to the PDFPageProxy.getOperatorList method (issue 13704)

With this patch, the `PDFPageProxy.getOperatorList` method will now return `PDFOperatorList`-instances that also include Annotation-operatorLists (when those exist). Hence this closes a small, but potentially confusing, gap between the `render` and `getOperatorList` methods.

Previously we've been somewhat reluctant to do this, as explained below, but given that there's actual use-cases where it's required probably means that we'll *have* to implement it now.
Since we still need the ability to separate "normal" rendering operations from direct `getOperatorList` calls in the worker-thread, this API-change unfortunately causes the *internal* renderingIntent to become a bit "messy" which is indeed unfortunate (note the `"oplist-"` strings in various spots). As-is I suppose that it's not all that bad, but we may want to consider changing the *internal* renderingIntent to e.g. a bitfield in the future.

Besides fixing issue 13704, this patch would also be necessary if someone ever tries to implement e.g. issue 10165 (since currently `PDFPageProxy.getOperatorList` doesn't include Annotation-operatorLists).

*Please note:* This patch is *also* tagged "api-minor" for a second reason, which is that we're now including the Annotation-id in the `beginAnnotation` argument. The reason for this is to allow correlating the Annotation-data returned by `PDFPageProxy.getAnnotations`, with its corresponding operatorList-data (for those Annotations that have it).

src/core/annotation.js

@@ -702,7 +702,13 @@ class Annotation {
 
     return resourcesPromise.then(resources => {
       const opList = new OperatorList();
-      opList.addOp(OPS.beginAnnotation, [data.rect, transform, matrix]);
+      opList.addOp(OPS.beginAnnotation, [
+        data.id,
+        data.rect,
+        transform,
+        matrix,
+      ]);
+
       return evaluator
         .getOperatorList({
           stream: appearance,
@@ -1307,6 +1313,7 @@ class WidgetAnnotation extends Annotation {
 
         const transform = getTransformMatrix(this.data.rect, bbox, matrix);
         operatorList.addOp(OPS.beginAnnotation, [
+          this.data.id,
           this.data.rect,
           transform,
           matrix,