fullsend: allow triage-level users to trigger /fs-review

Problem

The fullsend reusable dispatch (reusable-dispatch.yml) gates all /fs-review and /fs-fix commands behind has_write_permission, which requires admin, maintain, or write repo access. Users with triage permission cannot trigger agent runs — their commands are silently ignored.

This makes sense for /fs-fix (pushes commits), but /fs-review is read-only analysis that posts a review comment. Requiring write access for a read-only operation is overly restrictive.

Context

Discovered on rhdh-plugin-export-overlays#2778 — a contributor with triage permission commented /fs-review multiple times with no effect, while an admin's identical comment triggered the run immediately.

The repo has 13 users at triage level who cannot trigger reviews, vs 84 users at write+ who can.

Proposed fix

Add a min_permission input to reusable-dispatch.yml (defaulting to write for backwards compatibility) that repos can override in their shim workflow:

# .github/workflows/fullsend.yaml
uses: fullsend-ai/fullsend/.github/workflows/reusable-dispatch.yml@v0
with:
  min_permission: triage   # allow triage users to trigger /fs-review

Or, lower the permission floor for /fs-review specifically (since it's read-only), while keeping write for /fs-fix.

Workaround

Grant the user write access to the repo.

Start by reading reusable-dispatch.yml, focusing on the has_write_permission gate for /fs-review and /fs-fix, then inspect the referenced shim workflow example in the issue. Define whether the change uses a configurable permission floor or separate floors by command. Done means triage users can trigger read-only reviews, write access remains required for fixes, and the default preserves existing behavior.