fix(registry): quote keys, dedupe tags, and document sourcing order; CI commits regenerated registry

- Quote both keys and values in the generated __fish_config_op_registry.fish
  keys array so a future identity/tag containing a glob-special character
  (*, ?, [) can't be silently dropped by fish's set, desyncing the
  positionally-paired keys/values arrays.
- Deduplicate the tag list per site in build_registry() so an identity
  collision across sources (e.g. auto-pull tagged autoexec/sync in both
  functions/auto-pull.fish and conf.d/auto-pull.fish) no longer produces a
  duplicated tag in the committed registry.
- Add a comment to the generated file's header noting it must sort first
  among conf.d/*.fish guard-callers, since that ordering is currently
  implicit in the filename rather than stated anywhere.
- CI's auto-commit step now also stages conf.d/__fish_config_op_registry.fish
  alongside the docs it already regenerates, so a # COMPONENT header change
  pushed without a manual __fish_config_op_registry_rebuild self-heals
  instead of silently drifting from what CI just regenerated.

.github/workflows/build-docs.yml

@@ -78,7 +78,7 @@ jobs:
         run: |
           git config user.name  "Gitea Actions"
           git config user.email "actions@gitea"
-          git add docs/fish-config.md docs/fish-config.1
+          git add docs/fish-config.md docs/fish-config.1 conf.d/__fish_config_op_registry.fish
           git diff --cached --quiet && echo "No changes to commit" && exit 0
           git commit -m "chore(docs): regenerate manual and man page"
           git push