feat(runtime-host): discover coordination relays automatically

[M4n5ter]

English

Summary

• Discover public Circuit Relay v2 candidates through a bounded, client-only IPFS Amino DHT swarm
• Keep reservation authority in the main peer endpoint, prefer manually configured relays, and publish only accepted reservations
• Enable best-effort discovery by default for managed peer Hosts, with explicit Desktop and CLI opt-out

Refs #3842

Verification

• Rust formatting, Clippy, 9 native tests, cargo-deny, dependency and notice gates
• Build, typecheck, lint, format, Knip, ASF source/header, release, Astryx, and Storybook gates
• Full Runtime Host suite (1,347 passed) and Desktop suite (1,672 passed)
• Focused management, framing, native-peer, and SSH suites (60 passed)
• A real public-network run accepted reservations from two distinct Relay v2 peers
• Desktop Settings flow inspected in the development build

UI

AI use

Select exactly one:

• No generative tool made a substantive contribution
• Generative tooling made a substantive contribution

Tool(s) and scope: OpenAI Codex implemented and verified the change under M4n5ter's direction and review

Checklist

• Tests cover the change and fail without it
• Lint, format, typecheck and the affected suites pass locally

Does this PR entail a change in behavior?

• Yes — described under Summary above
• No

简体中文

摘要

• 通过有界且仅作客户端使用的 IPFS Amino DHT swarm 发现公共 Circuit Relay v2 候选节点
• reservation authority 仍只属于主 peer endpoint；手动配置的 Relay 优先，且只发布已接受 reservation 的节点
• managed peer Host 默认启用尽力而为的自动发现，并在 Desktop 与 CLI 提供明确的关闭方式

关联 #3842

验证

• Rust 格式、Clippy、9 项 native 测试、cargo-deny、依赖和 notice 门禁
• build、typecheck、lint、format、Knip、ASF source/header、release、Astryx 和 Storybook 门禁
• 完整 Runtime Host 测试（1,347 项通过）和 Desktop 测试（1,672 项通过）
• management、framing、native peer 与 SSH 定向测试（60 项通过）
• 真实公网测试成功获得两个不同 Relay v2 peer 的 reservation
• 已在开发构建中检查 Desktop 设置流程

界面

AI 使用

OpenAI Codex 在 M4n5ter 的指导和审核下实现并验证了本次变更

检查清单

• 测试覆盖本次变更，且在缺少实现时会失败
• lint、format、typecheck 与受影响的测试套件均已在本地通过

本 PR 是否改变行为？

• 是——已在摘要中说明
• 否