retrofit data repin

Re-point one corpus data file's anchor-op at an opid you name.

The recourse of `data-file-anchor-unresolved`: an anchor names an opid
exactly, so when revising an op's content or removing the op drops that opid
from the oplog, a data file anchored on it is orphaned and this verb re-points
the file. One invocation re-pins every record in that file.

Only an orphaned file is eligible. A file whose anchor still resolves is
history-bound at a live op, and moving it is a relocation rather than a
repair; capture the rows at the new point instead.

The target is required: pass the opid, an anchor ref (`last`,
`seal`, each with optional `^`/`~N`) or a 1-12 hex opid prefix.
The resolved 12-hex opid is what is written; the literal spelling never is.

A re-pinned record that carried a witness is re-witnessed: one
WitnessReferenceData entry is appended at the new anchor, over the rewritten
bytes. An unwitnessed record stays unwitnessed; --dry-run appends nothing.

Usage:
  retrofit data repin <file> [flags]

Flags:
      --anchor-op <target>    the <target> opid to re-pin on: an opid, an anchor ref (`last`, `seal`, with `^`/`~N`) or a 1-12 hex prefix
      --data-root data_root   root that overrides the schema's data_root
      --dry-run               rehearse the re-pin without writing
  -h, --help                  help for repin
      --help-all              show extended help (vocabulary, semantics, caveats)

Global Flags:
      --as string        output mode: text | json (default "text")
  -C, --chdir string     treat <dir> as the working directory for the entire run
      --config string    retrofit.toml path (overrides discovery; also accepts $RETROFIT_CONFIG)
  -f, --file string      oplog file path; selects a registered [[schema]] path (overrides discovery)
      --no-consolidate   render every advisory occurrence instead of collapsing repeats
  -q, --quiet count      suppress the advisory tier on stderr; stack (-qq) to drop it whole (errors and results still print)
  -v, --verbose          reveal info-tier advisories on stderr

Docs: https://docs.retrofit.sh/current/commands/retrofit-data-repin/