docs: document deprecation rationale for getPomFile/setPomFile (apache#11680)

* docs: document deprecation rationale for getPomFile/setPomFile

* docs: clarify deprecation replacement for Language.SCRIPT

* docs: fix deprecation text format in maven.mdo

* docs: remove redundant deprecation tag for Language.SCRIPT

* docs: restore 'since' in @deprecated annotation and remove redundancy

* docs: restore {@link} reference in deprecation note

Author: anukalp2804

api/maven-api-model/src/main/mdo/maven.mdo

@@ -400,13 +400,18 @@
      *
      * @return The POM file from which this model originated or {@code null} if this model does not belong to a local
      *         project (e.g. describes the metadata of some artifact from the repository).
+     *
+     * @deprecated Use {@link #getPomPath()} instead.
      */
-    @Deprecated
+    @Deprecated(since = "4.0.0")
     public java.io.File getPomFile() {
         return (getDelegate().getPomFile() != null) ? getDelegate().getPomFile().toFile() : null;
     }
 
-    @Deprecated
+    /**
+     * @deprecated Use {@link #setPomPath(Path)} instead.
+     */
+    @Deprecated(since = "4.0.0")
     public void setPomFile(java.io.File pomFile) {
         update( getDelegate().withPomFile(pomFile != null ? pomFile.toPath() : null));
     }