[v24.2.x] [CORE-9029] schema_registry/protobuf: Rewrite and fix Normalization

[vbotbuildovich]

Backport #25094 to branch v24.2.x. This issue was created as a placeholder because the original PR's commit(s) could not be automatically cherry-picked.
Here are the commands to execute:

git checkout v24.2.x
git checkout -b manual-backport-25094-v24.2.x-350
git cherry-pick -x 30f9e63f88 5813e2c210 6e83075e6f e8c3909c40 040514254d 448e2a4951 740ea83432 192bc2ce3e fa0dd711c4 cec240f87b 9677240dd3 bb868b3d20 21c8ad7226 3444e8464d 3abd347a3b 4a6d3bed18 51c5152e78 664e3826bf 6785b67207 3e4e26a573

git push origin manual-backport-25094-v24.2.x-350
gh pr create \
  --title "[v24.2.x] [CORE-9029] schema_registry/protobuf: Rewrite and fix Normalization" \
  --base "v24.2.x" \
  --label "kind/backport" \
  --head "manual-backport-25094-v24.2.x-350" \
  --draft \
  --repo "redpanda-data/redpanda" \
  --milestone "v24.2.x-next" \
  --body "Backport of PR https://github.com/redpanda-data/redpanda/pull/25094 "

JIRA Link: [CORE-9173](https://redpandadata.atlassian.net/browse/CORE-9173)