Research llama.cpp runtimes + SGLang; fix AGENTS.md OKF spec link

Fan out subagents to compare mainline llama.cpp, charlie12345/ROCmFPX,
and ik_llama.cpp, then add their findings to the project knowledge base:
- docs/Research/Llama Cpp Runtimes.md  (positioning + quantization + server fit)
- docs/Research/Llama Cpp Code Diff.md (code-level quant diff, table, recommendations)
- docs/Research/SGLang.md              (what SGLang is, comparison, our-boxes fit)
- docs/Research/index.md               (Research progressive-disclosure index)
Cross-linked from docs/index.md (root) and docs/LLM/index.md.

AGENTS.md:
- Add Documentation Authoring section: docs/ is an OKF bundle; point doc authors
  at the canonical spec in the system-config knowledge base
  (~/.pi/agent/docs/references/okf-spec.md), not the orphaned
  docs/references/okf-spec.md; consolidate read-index/one-concept-per-file/
  progressive-disclosure/citation rules.
- Map AGENTS.md to docs_completeness.bats in the focused pre-commit hook (it was
  last committed before the hook existed and had no mapping).

docs/LLM/index.md

@@ -109,6 +109,12 @@ MTP draft + Turbo4 V cache, 262K ctx / 1 slot]
 - [[Pipeline Parallelism/index]] — index of multi-node inference research. The PP
   pair is retired. These pages are research history.
 
+## Runtime Research (llama.cpp family)
+
+- [[Llama Cpp Runtimes]] — mainline vs charlie12345/ROCmFPX vs ik_llama.cpp: positioning, quantization, server fit
+- [[Llama Cpp Code Diff]] — code-level quantization diff of the three runtimes + server recommendations
+- [[SGLang]] — the structured-generation serving engine; when it fits Dankserver (3090) vs Dankclaw (Strix Halo)
+
 ## Related
 
 - [Project knowledge base](../index.md) — the Podman app stacks on the same