"Reopen in Container" triggers template wizard instead of opening existing devcontainer.json

Title: "Reopen in Container" triggers template wizard instead of opening existing devcontainer.json

Extension version: Dev Containers 0.447.0

VS Code version: 1.110.0

OS: Linux (Arch) arm64, kernel 6.18.15-1-1-ARCH

Docker version: 29.2.1

Description:

When running "Dev Containers: Reopen in Container" with a valid .devcontainer/devcontainer.json already present, the extension ignores the existing config and instead launches the "Add Dev Container Configuration Files" template wizard, asking to overwrite the existing file at the end. The container never opens.

Steps to reproduce:

Open a project with an existing .devcontainer/devcontainer.json
Run Ctrl+Shift+P → "Dev Containers: Reopen in Container"
Observe: template wizard appears instead of container starting
Wizard asks to overwrite existing devcontainer.json at the end
Expected behavior: Container starts using the existing devcontainer.json.

Actual behavior: createDevContainerConfig_v2 is entered and the template wizard runs. The container is never started.

Evidence from extension log:

[2026-03-06T20:50:54.496Z] Entering createDevContainerConfig_v2
This is logged in response to "Reopen in Container", followed immediately by the Rust template wizard (ghcr.io/devcontainers/templates/rust) being applied.

Workaround: Using the devcontainer CLI directly works correctly:

npx @devcontainers/cli up --workspace-folder
This confirms the devcontainer.json is valid and the issue is isolated to the extension's command handling.