chore(deps): raise the Pi compatibility floor to 0.84.3

[JS-banana]

Problem

OpenPI documents and freezes Pi 0.84.1 even though provider correctness now depends on host contracts first released in Pi 0.84.3. Caret development ranges allow newer patches, but the frozen lock and existing CI lanes do not continuously prove either the intended floor or the newest locked patch.

Closes #328. This is the project-wide compatibility follow-up to #269; that provider PR intentionally keeps package.json and bun.lock unchanged.

Value

The repository gains one explicit, reviewable Pi support boundary instead of handling version-sensitive provider behavior case by case. Contributors test against the current compatible patch, while CI prevents accidental use of APIs newer than the documented minimum.

Approach

• Raise the three Pi development ranges from ^0.84.1 to ^0.84.3 and regenerate bun.lock, which currently resolves the compatible Pi family at 0.84.4.
• Keep runtime peer dependencies at *; Pi remains the owner of the host packages used by installed OpenPI packages.
• Preserve the existing locked Node 22 and Node 24 check names, and add a Node 22 minimum-version lane.
• In the minimum lane, transiently override and verify all seven resolved Pi packages at exactly 0.84.3, then restore the publishable manifest before running the normal checks, tests, source-install smoke, and packed-package smoke.
• Document the support boundary and its evidence in Decision 0003 and README, and enforce the declared development floor with the package contract test.

Validation

• NPM_CONFIG_REGISTRY=https://registry.npmjs.org bun install --frozen-lockfile — passed with locked Pi 0.84.4.
• bun run check — passed on locked Pi 0.84.4 and an isolated exact Pi 0.84.3 family.
• PI_CODING_AGENT_DIR="$(mktemp -d)" bun run test — both versions passed 1,115 of 1,116 Node tests with the single Windows-only test skipped, plus 30/30 Vitest tests.
• Source-install package discovery smoke — passed on Pi 0.84.3 and 0.84.4.
• Packed-package loading without optional peers — passed on Pi 0.84.3 and 0.84.4.
• git diff --check — passed.

Impact

Users and contributors must use Pi 0.84.3 or newer for the documented support boundary. No model-visible tools or context, runtime provider behavior, or persisted configuration/data change in this PR. The lockfile moves normal development to Pi 0.84.4 and its compatible transitive dependency graph; CI gains one full minimum-version lane and therefore additional runtime.

[JS-banana]

#330 已支持，本 PR 关闭