Host plugin failures are invisible in dsh web: a throwing or non-effect apply() marks the fiber FAILED with no output, and TypeError('Invalid effect') names neither the plugin nor the value

[longjucheng]

中文摘要 — 宿主侧插件 apply 抛错时 Fiber._reload 捕获、ctx.logger.error、置 FAILED、不重抛（vendor/cordis/src/fiber.ts:646–684）；dsh web 没有 logger 导出（#5145），所以终端没有任何输出。apply 返回一个普通对象走同一条路，错误只有 Invalid effect，不带插件名和返回值类型。客户端 Loader 的对应问题见 #7891。

Summary

A host plugin whose apply() throws, or returns a value Cordis cannot collect as an effect, is marked FAILED; dsh web prints nothing.

Reproduction

1. Link a plugin into the web profile (dsh plugin --profile web add link:./plugin).
2. Make apply(ctx) throw, or make it return a plain object (apply: ctx => helper(ctx) where helper returns { … }).
3. Reload. The plugin's tools and listeners are absent; the terminal shows no line.

Current behavior

• Fiber._reload awaits _execute, catches the throw, calls this.ctx.logger.error(reason), sets _error, unloads the effects registered so far and leaves the fiber FAILED without rethrowing (vendor/cordis/src/fiber.ts:646–665). With no exporter in the web profile (Two verified cordis logger bugs: warnings never reach the buffer, and exporter disposal removes the wrong exporter #5145) the logger line has no sink.
• _execute (fiber.ts:357–398) collects a function, awaits a thenable, iterates an iterable, and throws TypeError('Invalid effect') for any other non-nullish value. The message carries neither the fiber's plugin name nor the value's type.

Expected behavior

• A fiber that fails in a loaded profile produces one line in dsh web's terminal with the plugin id and the error message (cf. Client plugin-boot failures are swallowed: “The client Loader did not provide an error message” (a plugin's rejected apply() → whole app into recovery mode) #7891 for the client Loader).
• Invalid effect names the fiber and the returned value's type or constructor.

Environment

• @deepseek-ai/dsh source checkout at tag dsh-v0.2.0-rc.1, dev launch pnpm dsh web (node --import tsx/esm apps/cli/src/bin.ts web)
• Node v22.23.1, macOS 15.7.5 (arm64)
• Store: ~230 session directories, ~90 MB zstd JSONL, pre-v4 logs (session.jsonl.zstd, .v2, .v3) present