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/command-modes.md

@@ -68,10 +68,10 @@ Every mode that executes refuses a plan whose approval in the approval log does
 
 | Flag | Behavior |
 |------|----------|
-| _(default)_ | Claude Code `/code-review` + `/security-review` (engine, via the Skill tool, never `--fix`), then brief-conformance + code-correctness reviewers in parallel, coordinator dedup + verdict, write `{project_dir}/review.md` with the required `verdict:`, decide with `lib/review/verdict-gate.mjs` (0 ALLOW, or WARN with every counting MAJOR answered · 1 BLOCK · 2 never green), the operator answers each counting MAJOR (Phase 8.8), propose recurring finding classes as project memory (operator approves each line) |
+| _(default)_ | Claude Code `/code-review` + one security engine chosen by `lib/review/security-engine.mjs` (Claude Security where it is installed, else `/security-review`; with neither, security is "not measured", never 0 — the engine, via the Skill tool, never `--fix`), then brief-conformance + code-correctness reviewers in parallel, coordinator dedup + verdict, write `{project_dir}/review.md` with the required `verdict:`, decide with `lib/review/verdict-gate.mjs` (0 ALLOW, or WARN with every counting MAJOR answered · 1 BLOCK · 2 never green), the operator answers each counting MAJOR (Phase 8.8), propose recurring finding classes as project memory (operator approves each line) |
 | `--project <dir>` | **Required.** Path to trekplan project folder containing `brief.md`. Review is written to `{dir}/review.md` |
 | `--since <ref>` | Override "before" SHA for the diff range. Validated via `git rev-parse --verify` |
-| `--quick` | `/code-review` + code-correctness reviewer only; skip brief-conformance reviewer, `/security-review` and the coordinator's reasonableness filter except the brief-conflict rule — fast correctness-only pass |
+| `--quick` | `/code-review` + code-correctness reviewer only, no security engine; skip brief-conformance reviewer and the coordinator's reasonableness filter except the brief-conflict rule — fast correctness-only pass |
 | `--answers` | Only the operator's answers to the counting MAJORs (Phase 8.8) on the existing `{dir}/review.md`, then the verdict gate. No reviewer and no write of findings: it opens no new round and counts nothing against the cap |
 | `--validate` | Schema-only check on existing `{dir}/review.md` plus the verdict gate. No LLM calls. A 1.0 review without `verdict:` fails here (it still seeds a plan in soft mode) |
 | `--dry-run` | Print discovered scope + triage map; skip writes |