Keep options in a fixed order, and say which block a diff hunk is in

Options of a block (server options, a view, a zone) are listed and
written grouped by topic, alphabetical within a group, so the same
option is in the same place everywhere. Top-level statements keep the
order they were added in.

named.conf diffs add the enclosing blocks to each hunk header, like
git's function context: @@ -50,6 +49,8 @@ view "internal" {.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

internal/engine/deploy.go

@@ -335,5 +335,8 @@ func fileDiff(path string, old []byte, existed bool, new []byte, removed, secret
 	if d != "" && !strings.HasSuffix(d, "\n") {
 		d += "\n"
 	}
+	if strings.HasSuffix(path, ".conf") {
+		d = labelHunks(d, string(old), string(new))
+	}
 	return d
 }