chore(deps): update and align supported Pi baseline to 0.84.4 (#328)

[hasak21]

Problem

Closes #328. Relates to #269.

OpenPI previously expressed conflicting compatibility boundaries across repository assets:

• README.md documented support for Pi 0.84.1+;
• package.json specified ^0.84.1 for Pi devDependencies;
• bun.lock locked development and CI test environments to 0.84.1, while peerDependencies permitted any compatible version via *.

This baseline drift created behavioral divergence between fresh installations and frozen-lock CI environments. Specifically, upstream Pi introduced critical lifecycle fixes in v0.84.3 (compaction without token usage) and v0.84.4 (tool choice).

Value

• Unifies the verified development baseline and CI environment at Pi 0.84.4.
• Unlocks downstream provider implementations (e.g. PR feat(ai-providers): add Antigravity and Cursor OAuth providers #269) by allowing them to rely directly on Pi 0.84.3+/0.84.4+ native message-history context estimation and compaction without inventing custom workarounds or falsifying token usage.
• Retains OpenPI's core design stance: preserving Pi as the single source of truth for Session lifecycles.

Approach

1. Manifest & Lockfile Floor: Updated @earendil-works/pi-ai, @earendil-works/pi-coding-agent, and @earendil-works/pi-tui devDependencies in package.json from ^0.84.1 to ^0.84.4, with bun.lock locked to the verified release @0.84.4.
2. Published Peer Contract: Maintained peerDependencies: { ...: "*" } as standard for Pi packages without introducing an artificial runtime host-rejection layer.
3. Documentation Sync: Updated the Pi version badge and requirements in README.md to Pi 0.84.4+.
4. Decision Record: Added docs/decisions/0003-supported-pi-baseline.md (status: accepted, applies from this Decision forward) documenting the baseline decision, factual boundaries, and rejected alternatives.

Validation

• bun run check:config-contract -> passed (14 persisted fields)
• bun run check:discipline -> passed (12 append-only rows)
• bun run format:check -> 280 files checked, no fixes needed
• bun run lint -> 280 files checked, 0 errors, 0 warnings
• bun run typecheck -> passed (tsc --noEmit)
• bun run test (Node 22) -> 1108 passed, 1 platform skip; Vitest 30/30 passed (total 1138 passed tests, 0 failures)

Impact

• User-visible behavior: None directly. Users on Pi 0.84.4+ receive consistent native context estimation.
• Model-visible context/tools: None.
• Runtime/lifecycle: Enables Pi-native message-history compaction for providers with zero or output-only usage.
• Persisted config/data: None. Backward compatible with existing session records.
• Compatibility or risk: Low. Baseline aligned to verified Pi 0.84.4 release.

[tt-a1i]

复审 exact head eae25844f02dec3a372852ff042757ed5b933e6d。这个 PR 解决的是 Pi 版本基线漂移，价值在于让 provider 直接依赖 Pi 原生 compaction；方法是同步 devDependencies、lockfile、README 和 Decision。方向成立，但当前“enforce 0.84.3+”尚未被证据和发布合同证明。

Standards

2 项：Decision 仍是 proposed，却已经作为官方约束实施；适用范围又追溯到未被本 PR 改变的 OpenPI 0.1.0+。

Spec

2 项：发布包的 Pi peers 仍为 *，Pi managed install 还会 omit/忽略 peer 约束，因此旧 host 仍能安装加载；CI 只验证 lockfile 的 0.84.4，没有验证所声明的最低 0.84.3。

最小处理建议：先准确区分“声明/开发验证的支持下限”和“安装时强制拒绝旧宿主”；若没有 Pi-native 的宿主版本门，不要为了标题临时造一层。另补一个有界的 0.84.3 验证，或把已验证下限写成 0.84.4。当前 CI 全绿只能证明锁定版本 0.84.4。

[tt-a1i]

[P1] 这里只提高 devDependency，三个 Pi peer 仍是 *，现有 package-contract test 也固定了这个合同。当前 PR 因而只约束开发/CI；消费者使用 Pi 0.84.1 仍可安装和加载。Pi 的 managed npm 安装还使用 --omit=peer / --legacy-peer-deps，所以不要仅靠 peer range 就声称运行时拒绝。请把“enforce / published packages coherent”收窄为真实可证明的支持边界；只有存在受支持的 Pi-native 版本门时才声称强制。

[tt-a1i]

[P2] 本记录仍是 proposed，但同一 PR 已修改 README、manifest 和 lockfile 来执行它。docs/decisions/README.md 明确 proposed 不具权威性、accepted 才采用。合并采用时应标为 accepted；否则保持 proposed 并拆开实施。

[tt-a1i]

[P2] OpenPI 0.1.0+ 会把新下限追溯到已经发布、当时仍宣称支持 Pi 0.84.1 的历史版本。请把适用边界限定到本次实际发布版本或精确 source revision，避免静默改写历史承诺。

[hasak21]

Thanks for the thorough review and clear boundary guidance! @tt-a1i

I have updated the branch with commit 4dabc1d, addressing all review items:

1. Declared & Verified Baseline Alignment (0.84.4):
   • Aligned the manifest floor (package.json devDependencies to ^0.84.4), lockfile (bun.lock @ 0.84.4), README (Pi 0.84.4+), and Decision record to Pi 0.84.4+, ensuring the declared baseline matches our CI-verified lockfile evidence without unproven sub-version gaps.
2. Published Peer Contract & Enforcement Boundary:
   • Clarified in Decision 0003 and PR metadata that published packages retain standard peerDependencies: { ...: "*" } without inventing an un-Pi-native runtime rejection gate.
   • Reframed the PR scope from "enforcement" to updating and aligning the verified development/CI baseline.
3. Decision 0003 Metadata & Scope:
   • Updated decision-status: accepted to reflect adoption upon merge.
   • Constrained applies-to: OpenPI development and CI baseline from this Decision forward to avoid retroactively rewriting historical commitments.
4. Validation:
   • bun run check (config-contract, discipline, format, lint, typecheck) -> passed.
   • bun run test (Node 22) -> 1108 Node tests passed, 1 platform skip; Vitest 30/30 passed (total 1138 passed tests, 0 failures).

Please take another look when convenient!