docs(review): /trekreview chooses its security engine (E 3.2)

Phase 4.7 of /trekreview runs security-engine.mjs choose first. Claude
Security runs through its own skill (scan changes --base {before_sha}
--effort high); its cost question goes to the operator, and "No", a
question nobody can answer or a missing Workflow tool records it as not
run, never a fallback to /security-review. /security-review runs only
when choose picked it. Its report is converted by security-engine.mjs
convert, never transcribed; below_threshold is declined as
engine:below-threshold. With no engine the expected reviewer
security-engine never reports, so the verdict gate exits 2 and the
summary says "security: not measured" and why, never 0. --quick keeps no
security engine. The Engine summary line, the template's ran line, the
hard rules (the engine's report folder, scan changes only) and the
allowed-tools (Workflow) follow.

Engine prose follows in commands/trekexecute.md, docs/command-modes.md,
docs/architecture.md, CLAUDE.md, README.md, SECURITY.md and Handover 6:
Claude Security recommended, proprietary so called by name and never a
manifest dependency; without it /security-review; with neither "not
measured".

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

docs/architecture.md

@@ -9,7 +9,7 @@ Imported from `CLAUDE.md` via pointer.
 - `lib/util/{frontmatter,result,atomic-write,autonomy-gate}.mjs` — shared YAML-frontmatter parser + Result helpers + `atomicWriteJson(path, obj)` for tmp+rename writes + `--gates` flag parser (v3.4.0)
 - `lib/parsers/{plan-schema,manifest-yaml,arg-parser,jaccard,finding-id}.mjs` — pure parsers (no I/O), unit-tested. `manifest-yaml` extended in v3.4.0 with additive `skip_commit_check` + `memory_write` flags (forward-compat: unknown keys ignored)
 - `lib/review/{rule-catalogue,plan-review-dedup}.mjs` — version-pinned rule catalogue (18 keys) + Phase 9 inline dedup helpers (v3.4.0)
-- `lib/review/{verdict-gate,engine-findings,recurrence}.mjs` — the review gate (K7: 0 ALLOW, or WARN with every counting MAJOR answered · 1 BLOCK · 2 never green), Claude Code `/code-review` + `/security-review` findings → reviewer payload, recurring finding classes → operator-approved project-memory lines (review_version 1.2); `lib/review/fill-finding-ids.mjs` computes the coordinator's `@@ID_<n>@@` placeholders over `(file, line, rule_key)`; `lib/validators/brief-review-stamp.mjs` lets `/trekplan` skip a brief review `/trekbrief` already ran on the same text
+- `lib/review/{verdict-gate,engine-findings,security-engine,recurrence}.mjs` — the review gate (K7: 0 ALLOW, or WARN with every counting MAJOR answered · 1 BLOCK · 2 never green), Claude Code `/code-review` + `/security-review` findings → reviewer payload, the security engine chosen (Claude Security, else `/security-review`, else "not measured") and Claude Security's report converted (confidence `high` counts, the rest `below_threshold`), recurring finding classes → operator-approved project-memory lines (review_version 1.2); `lib/review/fill-finding-ids.mjs` computes the coordinator's `@@ID_<n>@@` placeholders over `(file, line, rule_key)`; `lib/validators/brief-review-stamp.mjs` lets `/trekplan` skip a brief review `/trekbrief` already ran on the same text
 - `lib/validators/{brief,research,plan,progress,session-state}-validator.mjs` — schema validators with CLI shims (`node lib/validators/X.mjs --json <path>`)
 - `lib/validators/architecture-discovery.mjs` — drift-WARN external-contract discovery for `architecture/overview.md`
 - `lib/validators/query-privacy-gate.mjs` — gates an outbound research query before it leaves the machine (no command calls it now: its callers were the removed STORM steps); the hard-block tier (secret-shaped strings) is not operator-overridable, so a query that trips it must be reformulated rather than forced through. CLI shim: `node lib/validators/query-privacy-gate.mjs "<query>"`