feat(vscode): configurable TUI location

[dotneB]

Issue for this PR

Closes #15503

Type of change

• Bug fix
• New feature
• Refactor / code improvement
• Documentation

What does this PR do?

Adds opencode.tuiLocation to the vscode extension. Defaults to 'editor' which keeps the previous behavior. Adds 'terminal' to spawn the TUI to vscode Terminal panel instead.

How did you verify your code works?

cd opencode\sdks\vscode
bun compile
[...]
npx @vscode/vsce package --no-git-tag-version --no-update-package-json --no-dependencies --skip-license -o dist/opencode.vsix 1.2.15
[...]

Then installed the vsix in vscode to validate that the default behavior was kept and that the new behavior properly spawned the TUI in the terminal panel.

Screenshots / recordings

In VSCode Setting UI

Checklist

• I have tested my changes locally
• I have not included unrelated changes in this PR

If you do not follow this template your PR will be automatically rejected.

[dotneB]

Technically not related to the configurable location. But that disposable was never disposed

[dotneB]

Running bun compile for the vscode ext gives

❯ bun compile
$ bun run check-types && bun run lint && node esbuild.js
$ tsc --noEmit
$ eslint src

D:\Development\opencode\sdks\vscode\src\extension.ts
    4:33   warning  Missing semicolon  semi
    6:33   warning  Missing semicolon  semi
[...]
  136:54   warning  Missing semicolon  semi
  140:26   warning  Missing semicolon  semi

✖ 50 problems (0 errors, 50 warnings)
  0 errors and 50 warnings potentially fixable with the `--fix` option.

This probably needs to be addressed in another PR

[github-actions]

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