frank-default-large: verify v2 main on build-qwen38 — flash-attn off required, MTP draft incompatible (ngram-mod fallback)

- Main model (v2 joined PLE layout, sha256 1e4160ca…) loads and serves on
  build-qwen38 only with --flash-attn off: the QSA indexer path calls
  ggml_fill on the F16-cast kq mask and aborts graph build (GGML_ASSERT
  F32 at ggml.c:5371). Verified live: model loaded, health 200, real
  completion.
- MTP draft head (agentionai FAST, 2.28 GiB) does not load on this binary:
  qwen4exp loader requires full per-layer blk.<il>.hc_attn_norm.weight,
  head carries only blk.48. Third confirmation (EasiiX Q8_0 + agentionai
  FAST vs kingjones STRIX_LEAN previously, now own-matched pair). Spec
  decoding runs ngram-mod only; head retained for a future compatible build.
- FLASH_ATTN=off and SPEC_TYPE=ngram-mod wired through env + serve script;
  runbook and AGENTS.md updated with the verified constraints.

scripts/serve-frank-large.sh

@@ -12,18 +12,18 @@
 # Model: Qwen3.8-Flash-Next base (qwen4exp MoE: 512 experts / 10 used,
 # 48 layers = 12 attention + 36 SSM, QSA indexer, hyper-connections, PLE
 # at layer 1) quantized Q4_0_ROCMFP4_FAST, imatrix-calibrated, 87.06 GiB.
-# The n-gram PLE table is split per head inside the single GGUF — fully
-# VRAM-resident, no sidecar, no --ngram-on-disk.  The model's own MTP
-# head (2.28 GiB, matched ROCmFP4-FAST quant) drives speculative decoding
-# at depth 3 (~66% draft acceptance).
+# The n-gram PLE table is a single per_layer_token_embd.weight tensor —
+# fully VRAM-resident, no sidecar, no --ngram-on-disk.
 #
 # Profile: card sampling table (temp 0.7, top_p 0.80, top_k 20, min_p 0.0,
 # presence 1.5 — non-thinking instruct) mixed with the validated
 # build-qwen38 serving profile: ctx 262144 x 1 slot, b 4096 / ub 4096,
-# t 16 / tb 16, f16 KV, fa on, cont-batching, prompt cache + 8 GiB
-# cache-ram + idle-slot cache, 16 ctx checkpoints, --fit off (auto-fit
-# segfaults on qwen4exp hyper-connection config).  MTP depth 3 (n-max 3
-# measured best; adaptive p-split measured worse, left off).
+# t 16 / tb 16, f16 KV, fa OFF (see KNOWN CONSTRAINTS in the env file:
+# flash-attn on aborts graph build on the QSA indexer path), cont-batching,
+# prompt cache + 8 GiB cache-ram + idle-slot cache, 16 ctx checkpoints,
+# --fit off (auto-fit segfaults on qwen4exp hyper-connection config).
+# Speculative decoding is ngram-mod only; the MTP head does not load on
+# build-qwen38 (loader requires blk.0.hc_attn_norm.weight it lacks).
 set -euo pipefail
 
 SCRIPT_DIR="$(cd -- "$(dirname -- "${BASH_SOURCE[0]}")" && pwd)"
@@ -37,9 +37,9 @@ fi
 
 # --- defaults (used when the env file does not set them) -------------------
 : "${LLAMA_BIN:=/home/dank/GitPackages/ROCmFPX/build-qwen38/bin/llama-server}"
-: "${MODEL_DIR:=/home/dank/models/agentionai-Qwen3.8-Flash-Next-ROCmFP4-FAST}"
-: "${MODEL_FILE:=Qwen3.8-Flash-Next-ROCmFP4-FAST-imatrix-v2-ple16.gguf}"
-: "${MMPROJ_PATH:=$MODEL_DIR/mmproj/mmproj-Qwen3.8-Flash-Next-f16.gguf}"
+: "${MODEL_DIR:=/home/dank/models/agentionai-Qwen3.8-Flash-Next-ROCmFP4-FAST/v2}"
+: "${MODEL_FILE:=Qwen3.8-Flash-Next-ROCmFP4-FAST-imatrix-v2.gguf}"
+: "${MMPROJ_PATH:=$MODEL_DIR/../mmproj/mmproj-Qwen3.8-Flash-Next-f16.gguf}"
 : "${CHAT_TEMPLATE_FILE:=$SCRIPT_DIR/chat-template.jinja}"
 : "${CHAT_TEMPLATE_KWARGS:={}}"
 : "${ALIAS:=frank-default-large}"
@@ -57,17 +57,15 @@ fi
 : "${CACHE_RAM:=8192}"
 : "${SLOT_SAVE_PATH:=$SCRIPT_DIR/slot-state}"
 : "${SPLIT_MODE:=none}"
-: "${FIT:=off}"
-: "${NGL:=999}"
+: "${FLASH_ATTN:=off}"
 : "${TEMPERATURE:=0.7}"
 : "${TOP_K:=20}"
 : "${TOP_P:=0.8}"
 : "${MIN_P:=0.0}"
 : "${PRESENCE_PENALTY:=1.5}"
 : "${REASONING:=on}"
-: "${REASONING_FORMAT:=deepseek}"
 : "${HSA_OVERRIDE_GFX_VERSION:=11.5.1}"
-: "${SPEC_TYPE:=draft-mtp,ngram-mod}"
+: "${SPEC_TYPE:=ngram-mod}"
 : "${DRAFT_MODEL_DIR:=/home/dank/models/mtp-Qwen3.8-Flash-Next-FAST}"
 : "${DRAFT_MODEL_FILE:=Qwen3.8-Flash-Next-MTP-ROCmFP4-FAST.gguf}"
 : "${SPEC_DRAFT_N_MAX:=3}"
@@ -154,7 +152,7 @@ exec /usr/bin/env \
     --batch-size "$BATCH_SIZE" \
     --ubatch-size "$UBATCH_SIZE" \
     --fit "$FIT" \
-    --flash-attn on \
+    --flash-attn "$FLASH_ATTN" \
     --cache-type-k "$CACHE_TYPE_K" \
     --cache-type-v "$CACHE_TYPE_V" \
     --threads "$NUM_THREADS" \