Backfill data columns (#15580)

**What type of PR is this?**

Feature

**What does this PR do? Why is it needed?**

Adds data column support to backfill.

**Acknowledgements**

- [x] I have read
[CONTRIBUTING.md](https://github.com/prysmaticlabs/prysm/blob/develop/CONTRIBUTING.md).
- [x] I have included a uniquely named [changelog fragment
file](https://github.com/prysmaticlabs/prysm/blob/develop/CONTRIBUTING.md#maintaining-changelogmd).
- [x] I have added a description to this PR with sufficient context for
reviewers to understand this PR.

---------

Co-authored-by: Kasey <kasey@users.noreply.github.com>
Co-authored-by: Claude <noreply@anthropic.com>
Co-authored-by: Preston Van Loon <preston@pvl.dev>

beacon-chain/sync/backfill/error.go

@@ -0,0 +1,9 @@
+package backfill
+
+import "github.com/pkg/errors"
+
+var errUnrecoverable = errors.New("service in unrecoverable state")
+
+func isRetryable(err error) bool {
+	return !errors.Is(err, errUnrecoverable)
+}