Expose missing Docker Compose polyglot APIs to TypeScript AppHosts

[sebastienros]

Summary

The current TypeScript/polyglot Docker Compose surface appears narrower than the underlying .NET API, which makes compose publishing scenarios fall back to workarounds.

Likely missing exports

• DockerComposeEnvironmentExtensions.ConfigureComposeFile(...)
• DockerComposeServiceExtensions.AsEnvironmentPlaceholder(...) helpers
• possibly DockerComposeEnvironmentResource.GetHostAddressExpression(...) if that is intended to be polyglot-usable

Inconsistent projection

ConfigureEnvFile(...) looks especially suspicious: the C# API metadata still marks it as ignored / not ATS-compatible, but TypeScript publish tests use compose.configureEnvFile(...) successfully.

Why this matters

TypeScript AppHosts can already use addDockerComposeEnvironment(...) and publishAsDockerComposeService(...), but without the missing compose helpers the publish surface is incomplete for real-world compose customization.

Pointers

• src/Aspire.Hosting.Docker/DockerComposeEnvironmentExtensions.cs
• src/Aspire.Hosting.Docker/DockerComposeServiceExtensions.cs
• src/Aspire.Hosting.Docker/api/Aspire.Hosting.Docker.cs
• tests/Aspire.Cli.EndToEnd.Tests/TypeScriptPublishTests.cs
• tests/PolyglotAppHosts/Aspire.Hosting.Docker/TypeScript/apphost.ts

[MihuBot]

I'm a bot. Here is a possible related and/or duplicate issue (I may be wrong):

• Support AsEnvironmentPlaceholder on DockerComposeEnvironmentResource #12009