frank-medium: swap the drafter to magnitudedev/Qwen3.8-27B-DSpark

DSpark (Q8_0, 1.27 GiB) replaces z-lab DFlash2 (1.92 GiB): same 5-layer
block-diffusion shape, Markov head instead of the candidate selector, and
block_size 7, so the draft depth drops 7 -> 6 (llama.cpp asserts
n_max <= block_size - 1).

The serve script's dspark branch never passed --spec-draft-model (only the
dflash branch did), so dspark was not deployable as written; the model file
gate now covers both types. Download script, env and the unit seam track the
new file and its exact byte count.

scripts/serve-frank-medium.sh

@@ -1,7 +1,7 @@
 #!/usr/bin/env bash
 # Serve ajgazin/Swift-Qwen3.8-27B-Uncensored-Dynamic-MTP-GGUF @ UD-Q8_K_XL as
 # frank-medium on Dankserver's two Radeon AI PRO R9700 (gfx1201), with the
-# z-lab DFlash2 block-diffusion drafter, using mainline llama.cpp.
+# magnitudedev DSpark block-diffusion drafter, using mainline llama.cpp.
 #
 # Runtime: llama.cpp master fb27a525 (2026-09-16), a gfx1201 HIP build that
 # bundles its own ROCm 7.14 runtime (RPATH $ORIGIN/../lib), produced by
@@ -117,7 +117,7 @@ fi
 SPEC_ARGS=()
 if [[ -n "$SPEC_TYPE" && "$SPEC_TYPE" != "none" ]]; then
     SPEC_ARGS=(--spec-type "$SPEC_TYPE" --spec-draft-n-max "$SPEC_DRAFT_N_MAX")
-    if [[ "$SPEC_TYPE" == *dflash* ]]; then
+    if [[ "$SPEC_TYPE" == *dflash* || "$SPEC_TYPE" == *dspark* ]]; then
         if [[ ! -r "$DRAFT_MODEL" ]]; then
             echo "missing or unreadable draft model: $DRAFT_MODEL" >&2
             exit 1