Doc audit: fix all broken links + correct stale facts across the KB

Fanned out 5 read-only doc-auditor subagents (one per service group) that
fact-checked the knowledge base against the live system + repo config,
researched official setup docs online, and verified progress. Applied:
- All 34 broken links fixed (real pages / external URLs / correct relative
  paths); 0 broken links remain. No .AGENTTRASH links (the 4 mentions are
  accurate descriptive text, not links).
- Fact-check fixes: Readarr retired (May 2026), Radarr v4->v6, Calibre
  9.2.1 live, Calibre-Web 0.6.25 live, Copyparty v1.20.21, LLM index
  ncmoe 38 + 786432 ctx, frank-default-small active (not frank-pp-worker),
  Hermes/SearXNG/Grafana hostnames, Loki/Alloy local images, Observability
  diagram (Promtail->Alloy), VLLM retired note, DFlash status, benchmark
  live-drift notes, Homepage test count 116.

docs/LLM/ciru-activefpx-promptforge.md

@@ -253,7 +253,7 @@ ngram draft costs its own forward pass / occupancy without adding enough
 accepted tokens on top of MTP. Baseline (no ngram) remains the production
 config (`--spec-type draft-mtp` only). Keep ngram-mod off.
 
-The harness lives at [scripts/bench-spec-stack.sh](../scripts/bench-spec-stack.sh);
+The harness lives at [scripts/bench-spec-stack.sh](../../scripts/bench-spec-stack.sh);
 it boots the v3 stack on a scratch port and reads authoritative
 `print_timing` lines. It requires the production service to be stopped.