benchmarks(agentic): default DSv4 recipes to v6 (060226) corpus

Removes the DSv4 carveout in resolve_trace_source that pinned DSv4 to
the older 052726 v5 corpus. With v6 (060226) validated on both b300 and
gb300 DSv4 runs, there's no reason to keep DSv4 on the older trace set.

  - benchmark_lib.sh: the model-prefix branch on MODEL_PREFIX==dsv4 is
    gone; default_loader is now 060226 unconditionally. WEKA_LOADER_OVERRIDE
    still works for any recipe that wants to pin an older or different
    variant (e.g. the 256k-capped flavor used by max_model_len-constrained
    setups).
  - dsv4_fp4_b300_vllm.sh: drops its now-redundant explicit
    WEKA_LOADER_OVERRIDE=...060226 export since that's the default now.

Effect: every DSv4 agentic recipe (b200_vllm, b300_vllm, fp8_h200,
mi355x_sglang, gb300_dynamo_vllm) automatically rides v6 with no
per-recipe edit needed.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: cquil11

benchmarks/benchmark_lib.sh

@@ -926,17 +926,12 @@ resolve_trace_source() {
     # scenario. Used by recipes whose servers have non-default context
     # caps (e.g. minimaxm2.5 at max_model_len ~256k can't replay the
     # unfiltered corpus and switches to the 256k-capped variant), or
-    # by recipes that want to pin a specific corpus generation rather
-    # than ride the model-prefix-aware default below.
+    # by recipes that want to pin an older corpus generation.
     #
-    # Default (no override) is model-prefix-aware:
-    #   DSv4 recipes      -> 052726 (v5 corpus, the original baseline)
-    #   everything else   -> 060226 (v6 corpus, newer CC versions)
-    # DSv4 stays on 052726 for continuity with prior published baselines.
+    # Default (no override): semianalysis_cc_traces_weka_with_subagents_060226
+    # (v6 corpus, newer CC versions). All recipes — including DSv4 — ride
+    # this default unless they opt out via WEKA_LOADER_OVERRIDE.
     local default_loader="semianalysis_cc_traces_weka_with_subagents_060226"
-    if [[ "${MODEL_PREFIX:-}" == "dsv4" ]]; then
-        default_loader="semianalysis_cc_traces_weka_with_subagents"
-    fi
     local loader="${WEKA_LOADER_OVERRIDE:-$default_loader}"
     local dataset
     case "$loader" in

benchmarks/single_node/agentic/dsv4_fp4_b300_vllm.sh

@@ -52,8 +52,6 @@ fi
 nvidia-smi
 
 # ---- Resolve traces and install deps ----------------------------------------
-# Opt this recipe out of the DSv4 052726 default; use the v6 corpus.
-export WEKA_LOADER_OVERRIDE=semianalysis_cc_traces_weka_with_subagents_060226
 resolve_trace_source
 install_agentic_deps