fix: preserve ACP missing-file errors for Kimi Plan

[lodystage]

Related issue

Companion Kimi ACP fix: LodyAI/acp-extension-kimi#12.

Problem / pressure

Enabling Kimi Plan can activate planning and then fail while reading the not-yet-created plan file. Lody currently sends that missing-file failure as an ACP internal error, so the adapter cannot distinguish it from other I/O failures and even disabling Plan can fail.

Summary

Map native ENOENT to ACP resource-not-found in the client file-read handler. Preserve session validation, line slicing, and all other I/O failures. Advance the Kimi source submodule to the companion fix, add regression coverage, document the filesystem boundary, and record the paired diagnosis in a bilingual note.

Visual explanation

missing plan file
  Lody read_text_file: ENOENT -> ACP -32002
    Kimi filesystem adapter: ACP -32002 -> ENOENT (companion fix)
      Plan status: active plan with empty content

Before / after

Before	After
Missing file becomes Internal error	Missing file returns resource-not-found
Engine cannot distinguish missing and unreadable files	Kimi companion translates only structured missing-file errors

Test plan

• CLI agent-client suite: 21 passed; regression failed before the fix.
• Kimi ACP suite: 174 passed; ACP typecheck and full CLI build passed.
• Rebuilt Kimi runtime: isolated stdio client successfully enabled, repeated, and disabled Plan with ACP file reads. No model requests.
• pnpm format, changed-file lint, docs check, and public-boundary check passed. Lint has existing warnings.
• Full pnpm check stopped on missing dependencies/type declarations in other workspace packages. Targeted CLI tests reused an existing dependency installation; this is not a clean full-workspace validation.

Delivery

This client fix and the Kimi adapter fix are both required. The checksummed managed runtime must be published and its manifest advanced before shipping the complete fix. This PR does not publish a production artifact or change the installed runtime.

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-09-20T12:03:09.255568Z	57dbb27	Draft marked ready

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