Plan 10 — `codex` + `opencode` adapters

[carlomigueldy]

Plan file: docs/superpowers/plans/2026-05-23-plan-10-codex-and-opencode-adapters.md
Tag at close: v0.0.10-plan-10
Depends on: Plan 05 (claude-code adapter)

Goal

Ship two more built-in adapters — @dycode/adapter-codex (structured flavor) and @dycode/adapter-opencode (interactive flavor with PTY). Prove the SDK's three-flavor model by having three real adapters in the registry.

Deliverable

• adapters/codex + adapters/opencode packages.
• Per-adapter concurrency caps honored by the scheduler.
• Fixture mock binaries for deterministic tests.
• Real-CLI end-to-end tests (skipped when CLI absent).
• F59–F66.

Out of scope (deferred to later plans)

• Community adapter quickstart docs → Plan 16
• Adapter marketplace UI → out of scope for v1
• Per-task adapter overrides → out of scope until v1.1

Workflow

• Branch from main via superpowers:using-git-worktrees: feat/plan-10-codex-and-opencode-adapters.
• One PR closes this issue — include Closes #<this issue's number> in the PR description.
• Update docs/superpowers/plans/README.md to move this plan from "not started" to "shipped" in the same PR.
• Final step is the close-out commit and git tag v0.0.10-plan-10.
• All 5 quality gates apply (CONTRIBUTING.md).