fix: remove __DCP_CONTEXT_HANDLED__ throw that leaked to error logs (#296)

[ranxianglei]

Problem (Issue #296)

/acp commands throw Error: __DCP_CONTEXT_HANDLED__ which leaks to the opencode error log. In opencode 1.18.18, this produces level=ERROR entries for every /acp invocation.

Reported by @BsoBird on opencode 1.18.18 + ACP 1.14.16.

Root Cause

The command handler in hooks.ts threw new Error("__DCP_CONTEXT_HANDLED__") after handling /acp commands (lines 295, 299). This sentinel was meant to abort command processing, but opencode catches and logs it as an error.

Fix

Replace both throw new Error("__DCP_CONTEXT_HANDLED__") with return. Commands deliver output via sendIgnoredMessage (writes directly to session via client.session.prompt), so the hook can return normally without side effects.

Verification

• TypeScript: 0 errors
• Tests: 977 pass, 0 fail (added regression test)
• Build: 391.50 KB
• Deployed locally

[github-actions]

📦 Built Plugin Artifact

Branch: 2026-08-13_fix-dcp-context-handled-error (84039f2)

Option A — Install from npm PR tag (recommended)

opencode plugin opencode-acp@pr-297 --global

Each push to this PR publishes a new version under the pr-297 npm tag.

Option B — Install from GitHub

opencode plugin "github:ranxianglei/opencode-acp#2026-08-13_fix-dcp-context-handled-error" --global

Option C — Download artifact

1. Download the artifact from the Actions run
2. Extract the tarball and install:

tar xzf opencode-acp-pr297.tgz
cp -r package/dist ~/.cache/opencode/packages/opencode-acp@latest/node_modules/opencode-acp/dist

3. Restart opencode to pick up changes.

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This comment is automatically updated on each push.