chore(dankclaw): reclaim 510G of retired payloads; fix a stale fallback

The disk was at 93% with 137G free. Nine retired payloads are now moved
to ~/.AGENTTRASH/20260928-retired-models/ with a MANIFEST.md giving a
restore command per item — moved, not deleted, and nothing is freed until
the purge is approved. Every one maps to a runtime already retired in the
runbook index.

Only the .gguf was taken from Qwen3.8-27B-UD-Q8_K_XL/: the live
frank-large DFlash2 drafter lives in that directory and stays put. The
manifest warns against restoring the directory wholesale.

Kept: checkpoints/ (23G) — unreferenced by the repo, but ComfyUI is live
and its workflows were not searched, so it is not confirmed dead. Also
logs/, because x4e-run.log is a SPARSE file (3.3G apparent, 4K real) and
frees nothing.

The reference check caught a live bug: serve-frank-small.sh's fallback
MODEL_DIR still pointed at the retired GSQ-RCO payload frank-small served
on 2026-09-16/17. frank-small.env has always overridden it, so the drift
was invisible — but a missing or unreadable env file would have turned a
config problem into a "missing asset" naming a model that is no longer
there. Repointed at Gemma4-12B-QAT/, which the env file already sets.

Not taken, by request: podman images (279G reclaimable, 95%) and the
uv+pip caches (73G). Together 352G of regenerable garbage, larger than
what was reclaimed here.

The 29.3G payload rollback target went with the rest, so the payload-only
rollback is now a re-fetch first; the runbook and AGENTS.md say so.

serverAppConfigs-docs/LLM/frank-large-gufo-qwen38-27b.md

@@ -276,12 +276,12 @@ The differences worth knowing:
 
 Two independent rollbacks, because two things changed on 2026-09-28:
 
-1. **Payload only** — repoint `MODEL_FILE`/`MODEL_DIR` in
-   `scripts/frank-large.env` at
+1. **Payload only** — repoint `MODEL_FILE` in `scripts/frank-large.env` at
    `/home/dank/models/Qwen3.8-27B-UD-Q8_K_XL/Qwen3.8-27B-UD-Q8_K_XL.gguf`
-   and redeploy. That directory is untouched on disk and the drafter already
-   lives in it. This is the fast way back to the stock Qwen weights on the
-   gufo runtime.
+   and redeploy. **The 29.3 GiB target was reclaimed on 2026-09-28**, so this
+   path now needs a re-fetch first: `scripts/download-frank-large.sh`, then
+   the env edit. The DFlash2 drafter was never touched and still lives in
+   that directory.
 2. **Engine** — [[frank-large-unsloth-qwen38-27b-q8xl]]: the unsloth b11030
    prebuilt is still at `/home/dank/GitPackages/unsloth-llama-b11030/`.
    Revert `RUNTIME_DIR` and the gufo-only tunables, restore the serve