feat(serve): set APEX I-Compact as default, harden benchmark workflow

Serving:
- make serve now launches Claude-distilled APEX 35B-A3B (16GB) with 2
  parallel slots and 256K context as the daily driver
- add serve-custom for ad-hoc model testing
- add flush-gpu to reclaim unified memory after stuck runs

Benchmarks:
- default Vulkan-only backends (ROCm trails at long context)
- add --backends filter to run-baseline.sh
- fix backend filter substring bug (grep -qFx for exact line match)
- fix model filter regex metacharacter bug (grep -qiF for literal)
- respect --tg in long-context tests instead of hardcoded n=32

ROCm bump to 7.2.1 (kernel 6.18.4+ patch); keep 7.2 as optional.

Catalog:
- add mudler APEX I-Compact (Claude-distilled 35B, 17GB)
- add 0xSero REAP-40 (pruned 122B-A10B, 46GB)
- update download instructions: hf download (huggingface-cli is gone)

scripts/benchmark/run-suite.sh

@@ -9,7 +9,7 @@ source "$SCRIPT_DIR/../../lib/format.sh"
 
 MODEL_DIR="$(data_dir models)"
 TAG="run"
-BACKENDS_FILTER=""
+BACKENDS_FILTER="llama-vulkan-radv"
 MODELS_FILTER=""
 SKIP_LONGCTX=false
 MAX_SIZE_GB=0
@@ -99,13 +99,14 @@ declare -A BENCH_PATHS=(
     [llama-vulkan-amdvlk]="/usr/sbin/llama-bench"
     [llama-rocm-6.4.4]="/usr/local/bin/llama-bench"
     [llama-rocm-7.2]="/usr/local/bin/llama-bench"
+    [llama-rocm-7.2.1]="/usr/local/bin/llama-bench"
     [llama-rocm7-nightlies]="/usr/local/bin/llama-bench"
 )
 
 available_backends=()
 for tb in "${!BENCH_PATHS[@]}"; do
     if echo "$existing" | grep -q "^${tb}$"; then
-        if [[ -z "$BACKENDS_FILTER" ]] || echo "$BACKENDS_FILTER" | tr ',' '\n' | grep -q "$tb"; then
+        if [[ -z "$BACKENDS_FILTER" ]] || echo "$BACKENDS_FILTER" | tr ',' '\n' | grep -qFx "$tb"; then
             available_backends+=("$tb")
         fi
     fi
@@ -130,7 +131,7 @@ for p in "${ALL_MODEL_PATHS[@]}"; do
 
     # Name filter
     if [[ -n "$MODELS_FILTER" ]]; then
-        if ! echo "$MODELS_FILTER" | tr ',' '\n' | grep -qi "$local_name"; then
+        if ! echo "$MODELS_FILTER" | tr ',' '\n' | grep -qiF "$local_name"; then
             continue
         fi
     fi
@@ -252,7 +253,7 @@ for MODEL_PATH in "${MODEL_PATHS[@]}"; do
                 UB_SIZE=2048; [[ "$BACKEND" == *vulkan* ]] && UB_SIZE=512
                 CMD_LC=(toolbox run -c "$BACKEND" -- "${ENV_ARGS[@]}" "$BENCH_BIN"
                     -ngl 99 -mmp 0 -m "$TOOLBOX_MODEL_PATH" -fa 1
-                    -p "$CTX_PROMPT" -n 32 -d "$CTX_DEPTH" -ub "$UB_SIZE" -r "$REPS_LONGCTX" "${BATCH_ARGS[@]}" "${KV_ARGS[@]}")
+                    -p "$CTX_PROMPT" -n "$TG_TOKENS" -d "$CTX_DEPTH" -ub "$UB_SIZE" -r "$REPS_LONGCTX" "${BATCH_ARGS[@]}" "${KV_ARGS[@]}")
                 if "${CMD_LC[@]}" > "$OUT_LC" 2>&1; then
                     log_success "Done"; tail -3 "$OUT_LC"
                 else