fix: set Code Editor TypeScript target to ES2020

[willeastcott]

Summary

• setCompilerOptions in the Code Editor's Monaco setup was missing target and lib, causing Monaco's TypeScript language service to fall back to ES5/ES6 defaults. This meant modern APIs like Array.prototype.includes() (ES2016) and Object.entries() (ES2017) showed type errors.
• Explicitly sets target to ScriptTarget.ES2020 and lib to ['es2020', 'dom'] to match the engine's build target.

Fixes #1731

Test plan

• Open the Code Editor
• Use Array.prototype.includes() in a script -- verify no type error
• Use Object.entries() in a script -- verify no type error
• Verify general IntelliSense and type checking still works correctly

[Copilot]

Pull request overview

This pull request aims to fix TypeScript type errors in the Code Editor by setting the Monaco TypeScript compiler target to ES2020. However, the PR also includes unrelated changes for signed URL handling in asset loading.

Changes:

• Sets Monaco TypeScript compiler options to target ES2020 with 'es2020' and 'dom' libraries to support modern JavaScript APIs like Array.prototype.includes() and Object.entries()
• Adds signed URL support for asset files and variants (unrelated to PR description)
• Adds signedUrls type definition to LaunchConfig (unrelated to PR description)

Reviewed changes

Copilot reviewed 2 out of 3 changed files in this pull request and generated 2 comments.

File	Description
src/code-editor/monaco/document.ts	Adds target: ES2020 and lib: ['es2020', 'dom'] to Monaco TypeScript compiler options to fix type errors for modern JS APIs
src/launch/assets/assets-sync.ts	Adds logic to use pre-signed CloudFront URLs for asset files and variants (unrelated to PR description)
modules/editor-api/external/types/config.d.ts	Adds optional signedUrls property to LaunchConfig type (unrelated to PR description)

Comments suppressed due to low confidence (1)

src/code-editor/monaco/document.ts:183

• The setCompilerOptions call is executed every time a document is loaded (in the 'documents:load' event handler). While the dynamic 'paths' option may need to be recalculated per document due to import map changes, the 'target' and 'lib' settings are static and don't need to be reset on every document load. Consider moving the static compiler options (target, lib, allowJs, checkJs, allowNonTsExtensions, esModuleInterop) to a one-time initialization outside this event handler, and only update the dynamic 'paths' option inside the handler. This would improve performance by avoiding unnecessary reconfiguration of Monaco's TypeScript language service.

        monaco.languages.typescript.javascriptDefaults.setCompilerOptions({
            allowJs: true,
            checkJs: true,
            allowNonTsExtensions: true,
            esModuleInterop: true,
            target: monaco.languages.typescript.ScriptTarget.ES2020,
            lib: ['es2020', 'dom'],
            paths: {
                'playcanvas': ['playcanvas.d.ts'],
                ...monacoImportPaths
            }
        });

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[Copilot]

Pull request overview

Copilot reviewed 1 out of 1 changed files in this pull request and generated 1 comment.

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