Bump version to 3.0.0-SNAPSHOT

Starting point for the 3.0 release line. Remove hubspot.build.moved.after property
as this branch is now the canonical 3.0 development branch.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: jasmith-hs

pom.xml

@@ -10,7 +10,7 @@
 
   <groupId>com.hubspot.jinjava</groupId>
   <artifactId>jinjava</artifactId>
-  <version>2.8.4-SNAPSHOT</version>
+  <version>3.0.0-SNAPSHOT</version>
 
   <name>${project.groupId}:${project.artifactId}</name>
   <description>Jinja templating engine implemented in Java</description>