[information-architecture] Stale Issues docs hide bot actor allowlist input

## Information Architecture Findings

### 1. Published Stale Issues docs omit the bot actor allowlist control
**Area:** Data presentation / Consistency
**Component(s):** `docs/workflows/gh-agent-workflows.md`, `docs/workflows/gh-agent-workflows/stale-issues.md`, `gh-agent-workflows/stale-issues-investigator/README.md`, `gh-agent-workflows/stale-issues-remediator/README.md`

**Problem:** Users who install Stale Issues from the published docs cannot discover the `allowed-bot-users` input in the Stale Issues page or the overview's standard input reference, even though both underlying workflows expose it. This is a concrete IA problem for repos whose stale issue comments or labels are produced by a bot actor other than the default `github-actions[bot]`: the control exists, but the primary setup surface hides it.

**Evidence:**
- The overview says all workflows accept standard optional inputs, but lists only `additional-instructions` and `setup-commands`: `docs/workflows/gh-agent-workflows.md:170-177`.
- The published Stale Issues page lists investigator inputs without `allowed-bot-users`: `docs/workflows/gh-agent-workflows/stale-issues.md:44-50`.
- The same page lists remediator inputs without `allowed-bot-users`: `docs/workflows/gh-agent-workflows/stale-issues.md:91-97`.
- The source investigator README exposes `allowed-bot-users` with default `github-actions[bot]`: `gh-agent-workflows/stale-issues-investigator/README.md:40-47`.
- The source remediator README exposes `allowed-bot-users` with default `github-actions[bot]`: `gh-agent-workflows/stale-issues-remediator/README.md:30-37`.
- Other published workflow pages do surface the same control, for example `docs/workflows/gh-agent-workflows/issue-triage.md:29`, `mention-in-issue.md:29`, `mention-in-pr.md:30`, `pr-review.md:29`, and `pr-actions-detective.md:32`.

**Suggested improvement:** Add `allowed-bot-users` to the Stale Issues investigator and remediator input tables, and consider adding it to the overview's standard inputs section or explicitly documenting it as a common bot-trigger control.

## Suggested Actions
- [ ] Add `allowed-bot-users` to the Stale Issues Investigator inputs table in the published docs.
- [ ] Add `allowed-bot-users` to the Stale Issues Remediator inputs table in the published docs.
- [ ] Update the overview input reference so users can discover common bot-actor controls from the central workflow catalog.

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Start by comparing the input tables in docs/workflows/gh-agent-workflows.md and docs/workflows/gh-agent-workflows/stale-issues.md with the source tables in gh-agent-workflows/stale-issues-investigator/README.md and gh-agent-workflows/stale-issues-remediator/README.md. Update the published Stale Issues tables and the overview reference so allowed-bot-users, its default, and the relevant common-input guidance are discoverable in all identified locations.

Written by the indexing model from the issue text.