docs: reflect rollback to v3 on frank-default-large (Kairic experiment retired)

AGENTS.md topology table + runtime sections, docs/index.md deployment
diagram, docs/kairic-edge.md (retired experiment, perf summary), and
docs/ciru-activefpx-promptforge.md (active again) all restored to the
v3 reality. Remaining Kairic references are inside the retired reference
page itself.

docs/kairic-edge.md

@@ -15,14 +15,25 @@ timestamp: 2026-08-22
 
 # Kairic Edge IU4 Runtime on Dankclaw
 
-`frank-default-large` (port 52625) serves
+> **Retired 2026-08-22.** This experiment was deployed, benchmarks were
+> collected, and the service reverted to v3 the same day (operator
+> decision). `frank-default-large` serves v3 again. This page is kept as
+> the retired experiment's build runbook and reference.
+
+`frank-default-large` (port 52625) briefly served
 `jcbtc/Qwen3.8-27B-IU4-Kairic-Edge` through the Kairic Edge CIRU ROCmFPX
 llama.cpp runtime. The runtime routes qualified prompt and multi-token
 verification shapes through the RDNA 3.5 native
-`V_WMMA_I32_16X16X16_IU4` matrix instruction. This deployment replaced the
-v3 CIRU ActiveFPX PromptForge service on 2026-08-22. See
-[[ciru-activefpx-promptforge]] for the retired v3 runbook and rollback
-target.
+`V_WMMA_I32_16X16X16_IU4` matrix instruction. It was reverted to
+[[ciru-activefpx-promptforge]] (v3) on 2026-08-22.
+
+Performance summary of the experiment: the IU4 lane accelerated prefill
+1.5-2.3x over v3 at all depths, but prose decode was 15-26% slower
+(inherent to the release: the IU4 lane does not accelerate M1 target
+decode). Reasoning-off fast-greedy mode was ~8% faster per token than
+production chat, and roughly 2x faster per turn from halved output volume.
+The v3-era experience, including the 400 errors from the argmax fast path
+rejecting non-greedy requests, motivated the revert.
 
 ## Identity