[information-architecture] Continuous-improvement workflow set is inconsistent across onboarding docs

## Information Architecture Findings

### 1. Continuous-improvement workflow set is defined inconsistently across primary setup paths
**Area:** Consistency
**Component(s):**
- `README.md` (top-level)
- `docs/workflows/gh-agent-workflows.md`
- `gh-agent-workflows/README.md`
- `scripts/quick-setup.sh`

**Problem:**
Users are shown two different definitions of what `--continuous-improvement` installs, depending on where they start. The top-level onboarding surfaces omit `product-manager-impersonator` and `refactor-opportunist`, while the workflow README and installer script include both. This creates a navigation/hierarchy mismatch between “what docs say this set is” and “what the setup action actually does,” which can surprise users with unexpected scheduled workflows after installation.

**Evidence:**
- `README.md:26` — continuous-improvement list omits `product-manager-impersonator` and `refactor-opportunist`.
- `docs/workflows/gh-agent-workflows.md:27` — same omission in the docs-site workflow overview.
- `gh-agent-workflows/README.md:67-80` — `--continuous-improvement` list includes both workflows.
- `scripts/quick-setup.sh:122-136` — installer behavior includes both workflows.

**Suggested improvement:**
Establish one canonical continuous-improvement set and keep all onboarding entry points aligned with it. At minimum, synchronize:
1. `README.md` continuous-improvement list
2. `docs/workflows/gh-agent-workflows.md` recommended set
3. `gh-agent-workflows/README.md` set description
4. `scripts/quick-setup.sh` install set (or adjust docs to match if behavior is intentional)

## Suggested Actions
- [ ] Decide the canonical `--continuous-improvement` workflow set (including whether `product-manager-impersonator` and `refactor-opportunist` are intended defaults).
- [ ] Update all three documentation entry points to match the canonical set.
- [ ] Add a lightweight consistency check in CI (or docs lint) so workflow-set lists stay synchronized with `scripts/quick-setup.sh`.

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