docs(frank-medium): record the Qwen-Sharp v22.4.0 chat template

Runbook deployed-flags table and AGENTS.md now name the template
(froggeric v22.4.0, repo-tracked, terse by default) and the rollback
target; the stale qwen-fixed-v22.3.jinja row and the long-gone
MM_MERGE_ENGINE note are gone.

AGENTS.md

@@ -348,7 +348,9 @@ full window; the DFlash2 drafter's 2.1 GiB costs the pool vs MTP's 461,540).
 DFlash2 was A/B tested against MTP self-speculation on this checkpoint and
 wins on decode (100.0 vs 85.9 t/s) — see the runbook. Tools via `qwen3_coder`,
 reasoning via `qwen3` (the field is `reasoning`, not llama.cpp's
-`reasoning_content`), vision through the Gemma4 merge path.
+`reasoning_content`), vision through the Gemma4 merge path, chat template
+Qwen-Sharp v22.4.0 (froggeric, repo-tracked at `dankserver/frank-medium/`,
+terse system prompt by default).
 
 **The entrypoint is quantization-aware.** `radiance-entrypoint.sh` reads
 `quantization_config.quant_method` from the checkpoint's `config.json` and