docs: update CLAUDE.md and DECISIONS.md for completed 7-plan migration

Reflects Plan 7 (supervisor retirement) and brain_answer/brain_classify
addition. Supervisor MCP endpoint removed; brain now exposes HTTPS domain
with Dex JWT auth. Routing decisions documented for LLM berget→iguana chain.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

DECISIONS.md

@@ -72,23 +72,42 @@ Record *why* things are the way they are. Future-you will thank present-you.
 Plan 6 (Mode 2 routing pod, 2026-05-04) introduces a second consumer of
 the four cost-routable skill packages. The routing pod constructs each
 skill via `<pkg>.New(Config{...})` and hands it `routing.Router.Run` as
-the `CompleteFunc`. Plan 7 (supervisor retirement) MUST NOT delete the
-four packages.
+the `CompleteFunc`.
 
-**Plan 7's allowed deletions:**
-- `internal/skills/{tdd,spec,tier}/` (not consumed by the routing pod)
-- `cmd/supervisor/` (binary)
-- `Dockerfile` (supervisor's, at repo root — distinct from `Dockerfile.routing`)
-- supervisor manifests in the infra repo
-- NodePort `:30320`
-
-**Plan 7's preserved code:**
+**Preserved code (do not delete):**
 - `internal/skills/{review,debug,retrospective,trainer}/`
-- `internal/registry`
-- `internal/mcp`
-- `internal/exec/litellm.go`
-- `internal/routing/` (entirely new in Plan 6)
-- `cmd/routing/`
+- `internal/registry`, `internal/mcp`, `internal/exec/litellm.go`
+- `internal/routing/`, `cmd/routing/`
+
+---
+
+## Plan 7: supervisor pod retired (2026-05-12)
+
+**What was deleted:** `cmd/supervisor/`, `internal/skills/{tdd,spec}/`,
+root `Dockerfile`, supervisor k8s manifests (Deployment, Service, Ingress,
+NodePort 30320), `supervisor` entry removed from all `.mcp.json` configs.
+
+**Coverage:** `tdd`/`spec` → SKILL.md files in `~/dev/.skills/`; `review`,
+`debug`, `retrospective`, `trainer` → routing pod; `brain_*`/`session_log` →
+brain MCP; `tier` → `hyperguild tier` CLI.
+
+---
+
+## 2026-05-12 — brain_answer and brain_classify: LLM routing via berget.ai → iguana
+
+**Context:** Brain MCP returned raw BM25 excerpts with no synthesis. Adding
+LLM-backed tools enables Q&A and ingestion enrichment without a separate service.
+
+**Decision:** Two new MCP tools in the ingestion service (`ingestion/internal/mcp/`):
+- `brain_answer(query)` — BM25 top-10 → LLM synthesis → answer + sources
+- `brain_classify(text)` — LLM classifies doc into type/title/tags
+
+Primary LLM: berget.ai `gemma4:31b` (EU cloud, spend tokens while available).
+Fallback: iguana `gemma4:31b` (local Ollama). Reranker deferred to follow-up.
+Router lives in `ingestion/internal/llm.Router`; opt-in via `BRAIN_LLM_PRIMARY_URL`.
+
+**Consequences:** Brain becomes a knowledge assistant, not just a search index.
+When berget.ai tokens run out, flip `BRAIN_LLM_PRIMARY_URL` to iguana.
 
 ---