Rename script/fetch-policy to script/commit-current-upstream-policy-docs

sneak, on the PR: the script does more than fetch, and short names are
not wanted. The make target, the test names, the variables and the
messages take the new name. Behaviour is unchanged.

Model: opus-5-5

Makefile

@@ -1,4 +1,4 @@
-.PHONY: bootstrap setup test lint fmt fmt-check check docker hooks fetch-policy update-policy
+.PHONY: bootstrap setup test lint fmt fmt-check check docker hooks commit-current-upstream-policy-docs update-policy
 
 # Makefile targets are thin shims; the implementations live in script/
 # per the scripts-to-rule-them-all pattern (see the Entrypoints section
@@ -31,8 +31,8 @@ docker:
 hooks:
 	@script/install-precommit
 
-fetch-policy:
-	@script/fetch-policy
+commit-current-upstream-policy-docs:
+	@script/commit-current-upstream-policy-docs
 
 update-policy:
 	@script/update-policy