VS Code extension (sst-dev.opencode 0.0.13) fails on OpenCode v2: Unrecognized flag --port #51512

Description

After upgrading the OpenCode CLI from v1 to v2 (opencode v2.0.18), opening OpenCode from the VS Code extension (sst-dev.opencode v0.0.13, latest on the Marketplace as of 2025-12-28) fails immediately with:

ERROR
  Unrecognized flag: --port in command opencode

Root cause

The v2 CLI dropped the --port / --hostname flags that existed in v1 (server binding is now handled through the background service/serve subcommand architecture instead of top-level flags). The VS Code extension's bundled dist/extension.js still constructs its CLI invocation using the v1-style --port <n> flag, which v2's argument parser rejects outright.

Steps to reproduce

1. Install/upgrade to OpenCode CLI v2 (curl -fsSL https://opencode.ai/v2/install | bash)
2. Have sst-dev.opencode v0.0.13 installed in VS Code
3. Open a project in VS Code and launch OpenCode via the extension
4. Observe the Unrecognized flag: --port error at startup

Expected

The extension should either:

• Detect the CLI major version and adapt its launch invocation accordingly, or
• Drop --port and use v2's service/serve connection model (e.g. --server <url> / background service) when talking to a v2 CLI.

Environment

• OS: macOS (darwin 27.0.0)
• OpenCode CLI: v2.0.18 (installed via curl installer)
• Extension: sst-dev.opencode 0.0.13 (VS Code Marketplace, last updated 2025-12-28)

Happy to provide more logs if useful.