frank-small: four FULL 262144-token slots — the max that fits the card

CTX_SIZE=1048576 / PARALLEL=4: every slot gets the model's full trained
window. Measured fit arithmetic on the 3090: 1 full-context slot idles
at 11,996 MiB, 4 at 22,346 -> 3,450 MiB per slot, ~8,546 MiB fixed.
A 5th slot projects 25.8 GiB past the 24,576 MiB card, and the KV pool
allocates upfront, so 4 is the ceiling. Explicit CTX_SIZE bypasses --fit
on purpose: fit maximises the TOTAL pool and would divide a smaller
window across slots at parallel>1. The slot-grid seam now pins both the
full-window division and the budget inequality so a future capacity
bump fails pre-deploy, not in the boot allocation.

Audio verified while measuring: the mmproj's audio encoder transcribes
input_audio parts verbatim (JFK WAV sample). Header comments updated.

tests/frank_small_unit.bats

@@ -61,22 +61,28 @@ QUADLET_LARGE="$REPO_ROOT/dankclaw/frank-large/quadlet/frank-large.container"
     ! grep -q 'HALOGEN_VISION_TOWER' "$QUADLET_LARGE"
 }
 
-@test "frank-small quantizes KV to q8 and lets --fit size the context" {
-    local parallel cache_k cache_v ctx
+@test "frank-small's slot grid is full-window and fits the 24 GiB card" {
+    local parallel cache_k cache_v ctx fixed per_slot
     parallel="$(sed -nE 's/^PARALLEL=([0-9]+)$/\1/p' "$ENV_FILE")"
     cache_k="$(sed -nE 's/^CACHE_TYPE_K=(.+)$/\1/p' "$ENV_FILE")"
     cache_v="$(sed -nE 's/^CACHE_TYPE_V=(.+)$/\1/p' "$ENV_FILE")"
     ctx="$(sed -nE 's/^CTX_SIZE=([0-9]+)$/\1/p' "$ENV_FILE")"
-    [ -n "$parallel" ] && [ -n "$cache_k" ] && [ -n "$cache_v" ]
-    [ "$parallel" -ge 1 ]
-    # q8_0 KV is what fits the 24 GiB card beside 7.4 GiB of Q4_K_M weights +
-    # mmproj + sidecar: Gemma4's 16 kv heads x 512 dim cost 16 KiB per token
-    # per layer at q8, and the model's sliding-window pattern keeps the pool
-    # far below full-ctx x all-layers. The engine itself sizes the context:
-    # CTX_SIZE is unset, so the serve script passes --fit on.
-    [ -z "$ctx" ]
+    [ -n "$parallel" ] && [ -n "$cache_k" ] && [ -n "$cache_v" ] && [ -n "$ctx" ]
+    # Every slot must be the model's FULL trained window (262144), not a
+    # divided one -- CTX_SIZE is the total pool and --parallel divides it.
+    [ $((ctx / parallel)) -eq 262144 ]
+    [ $((ctx % parallel)) -eq 0 ]
     [ "$cache_k" = "q8_0" ] && [ "$cache_v" = "q8_0" ]
-    grep -q -- '--fit on' "$SERVE"
+    # Fit budget from the measured boot arithmetic on the 3090 (24576
+    # MiB): one full-context slot idles at 11,996 MiB, four at 22,346,
+    # so each slot costs (22346-11996)/3 = 3450 MiB and the fixed part
+    # (weights, projector, sidecar draft, compute buffers, CUDA context)
+    # is 11996-3450 = 8546 MiB. If the config asks for more slots than
+    # the card holds, this inequality fails before deploy instead of the
+    # KV allocation failing at boot.
+    fixed=8546
+    per_slot=3450
+    [ $((fixed + parallel * per_slot)) -le 24576 ]
     # Quantized KV on CUDA needs the GGML_CUDA_FA_ALL_QUANTS build option,
     # without which prefill collapses about 12x (see the CUDA lesson in
     # AGENTS.md). The build-cuda tree must carry it.