acp: set_config_option rejects a configured model selected right after session/new #52472

Description

Follow-up to #49630 / #50236, closed as fixed by #52286. On 2.0.21, which includes #52286, an ACP client that selects a model from opencode.json right after session/new still gets -32602 Invalid params: model not found. Sent two seconds later, the same request succeeds.

model.list answers before the location's plugins have registered config providers. So the catalog session/new loads lacks them, and the single reload in withReload before rejecting happens straight away, still too early. The config_option_update arrives a few hundred ms later. Editors cope; clients that pick a model during setup don't.

A fix that keeps catalog reads non-blocking: after that reload, keep following catalog refreshes until the value appears, plugin.updated marks activation done, or 5 s pass. I have it working with wire tests against v2, and can rebase it on #52471 if that helps.

Plugins

None, config only

OpenCode version

2.0.21 (also v2 at cf0c9fb from source)

Steps to reproduce

1. In an empty directory, an opencode.json with a custom provider: "provider": { "myprovider": { "npm": "@ai-sdk/openai-compatible", "options": { "baseURL": "http://127.0.0.1:9/v1", "apiKey": "x" }, "models": { "my-model": {} } } }
2. Run opencode acp there and send initialize, then session/new.
3. Immediately send session/set_config_option with configId: "model", value: "myprovider/my-model".

Expected: the model is selected. Actual: -32602 model not found: myprovider/my-model.

Screenshot and/or share link

No response

Operating System

Ubuntu (Linux)

Terminal

Raw stdio JSON-RPC client