Rename the scripts that update the policy files

script/commit-current-upstream-policy-docs is now
script/write-upstream-policy-files: it writes the policy files and
commits nothing. script/update-policy is now
script/commit-upstream-policy-files, and make update-policy is now
make commit-upstream-policy-files. test/update-policy.sh follows.
Behaviour is unchanged.

Model: opus-5-5

TODO.md

@@ -21,12 +21,12 @@ fmt-check, and commit.
 
 # Completed Steps
 
-- 2026-11-09: `script/commit-current-upstream-policy-docs` writes the vendored
-  policy files into a repo over HTTP, itself and `script/update-policy` among
-  them (https://git.eeqj.de/sneak/prompts/issues/165). `make update-policy` now
-  fetches the current `script/commit-current-upstream-policy-docs`, runs it and
-  commits without pushing. The template repositories get both scripts in their
-  own issues.
+- 2026-11-09: `script/write-upstream-policy-files` writes the vendored policy
+  files into a repo over HTTP, itself and `script/commit-upstream-policy-files`
+  among them (https://git.eeqj.de/sneak/prompts/issues/165).
+  `make commit-upstream-policy-files` replaces `make update-policy`. It fetches
+  the current `script/write-upstream-policy-files`, runs it and commits without
+  pushing. The template repositories get both scripts in their own issues.
 - 2026-11-09: `script/update-policy` and `make update-policy` update a repo's
   vendored policy files with one command
   (https://git.eeqj.de/sneak/prompts/issues/162). They fetch the files from