Bundle mode: SDK codegen doesn't include integration packages when aspire.config.json has multiple packages

[davidfowl]

Description

When a TypeScript AppHost project has multiple packages in aspire.config.json, the bundle mode SDK codegen generates a TypeScript SDK that only contains core Aspire.Hosting functions — the integration-specific functions (e.g., addUvicornApp from Aspire.Hosting.Python, addViteApp from Aspire.Hosting.JavaScript) are missing.

Reproduction

Create a TypeScript AppHost with aspire.config.json containing two packages:

{
  "packages": {
    "Aspire.Hosting.JavaScript": "...",
    "Aspire.Hosting.Python": "..."
  }
}

Run aspire run (or aspire start). The app crashes with:

❌ Uncaught Exception: builder.addUvicornApp is not a function
TypeError: builder.addUvicornApp is not a function

Key Observations

• Single package works: The TypeScript starter template (Aspire.Hosting.JavaScript only) generates a correct SDK with addExpressApp, addViteApp, etc. ✅
• Multiple packages fails: The Python starter template (Aspire.Hosting.JavaScript + Aspire.Hosting.Python) generates a SDK with only core Aspire.Hosting functions — NEITHER JavaScript nor Python functions are present. ❌
• This only affects bundle mode (native AOT CLI). SDK mode (dotnet run) works correctly.
• The generated SDK file is 16K lines but contains zero integration-specific methods.

Evidence from CI

• CI run: https://github.com/dotnet/aspire/actions/runs/23578767161
• TypeScriptStarterTemplateTests (1 package) → ✅ passes
• PythonReactTemplateTests (2 packages) → ❌ fails
• Workspace capture shows the generated aspire.ts only has Aspire.Hosting capabilities

Likely Root Cause

The BundleNuGetService.RestoreAndLayoutAsync calls aspire-managed nuget restore with multiple --package arguments. Either the restore or the layout step fails silently for multi-package scenarios, resulting in a libs directory that only contains the core Aspire.Hosting.dll without integration assemblies.

[davidfowl]

Closing — leaving the PR open to track this. The bundle mode multi-package issue will be addressed as part of #15574.