Update and rename 0000-fileorigin-fields.md to 0048-fileorigin-fields.md

rfcs/text/0000-fileorigin-fields.md → rfcs/text/0048-fileorigin-fields.md

@@ -1,8 +1,8 @@
-# 0000: File Origin Fields
+# 0048: File Origin Fields
 <!-- Leave this ID at 0000. The ECS team will assign a unique, contiguous RFC number upon merging the initial stage of this RFC. -->
 
 - Stage: **0 (strawperson)** <!-- Update to reflect target stage. See https://elastic.github.io/ecs/stages.html -->
-- Date: **TBD** <!-- The ECS team sets this date at merge time. This is the date of the latest stage advancement. -->
+- Date: **2024-10-15** <!-- The ECS team sets this date at merge time. This is the date of the latest stage advancement. -->
 
 <!--
 As you work on your RFC, use the "Stage N" comments to guide you in what you should focus on, for the stage you're targeting.