Fix TypeScript AppHost generated port ranges

[Eric Erhardt (eerhardt)]

Description

Fixes #16626

TypeScript AppHost scaffolding could generate dashboard, OTLP, and resource-service profile ports from a broad range that overlaps the Windows ephemeral port range. When that happened, DCP could fail to bind the configured dashboard HTTPS proxy while Aspire still reported that unreachable URL.

This consolidates the safe AppHost profile port ranges into a shared generator used by CLI templates, aspire init, and TypeScript AppHost scaffolding. The TypeScript scaffold now uses the same non-ephemeral bands as the other generation paths, and the regression test parses generated apphost.run.json to verify those ports stay out of the Windows ephemeral range.

Validation: Not run locally; restore.cmd was still installing the local SDK in the background when this PR was created.

Checklist

• Is this feature complete?
  • Yes. Ready to ship.
  • No. Follow-up changes expected.
• Are you including unit tests for the changes and scenario tests if relevant?
  • Yes
  • No
• Did you add public API?
  • Yes
    • If yes, did you have an API Review for it?
      • Yes
      • No
    • Did you add <remarks /> and <code /> elements on your triple slash comments?
      • Yes
      • No
  • No
• Does the change make any security assumptions or guarantees?
  • Yes
    • If yes, have you done a threat model and had a security review?
      • Yes
      • No
  • No
• Does the change require an update in our Aspire docs?
  • Yes
    • Link to aspire.dev issue:
      • New issue
  • No

[Copilot]

Pull request overview

This PR fixes TypeScript AppHost scaffolding occasionally generating dashboard/OTLP/resource-service ports in the Windows ephemeral range, which could prevent DCP from binding the dashboard HTTPS proxy and lead to Aspire reporting an unreachable dashboard URL. It centralizes “safe” profile port generation into a shared generator and applies it consistently across CLI templates, aspire init, and TypeScript scaffolding, with a regression test to keep the ports out of the ephemeral range.

Changes:

• Introduced AppHostProfilePortGenerator (shared source-linked utility) to generate profile ports from known non-ephemeral ranges.
• Updated TypeScript AppHost scaffolding, CLI templates, and aspire init to use the shared port generator.
• Added a TypeScript scaffolding regression test that parses apphost.run.json and asserts generated ports remain below the Windows ephemeral range and within the expected bands.

Reviewed changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
tests/Aspire.Hosting.CodeGeneration.TypeScript.Tests/TypeScriptLanguageSupportTests.cs	Adds a regression test that parses generated apphost.run.json and validates ports are within the safe ranges and below the Windows ephemeral range.
src/Shared/AppHostProfilePortGenerator.cs	Adds the shared port-range constants and generator returning an AppHostProfilePorts record struct.
src/Aspire.Hosting.CodeGeneration.TypeScript/TypeScriptLanguageSupport.cs	Switches TypeScript scaffold port generation to use AppHostProfilePortGenerator.Generate(...).
src/Aspire.Hosting.CodeGeneration.TypeScript/Aspire.Hosting.CodeGeneration.TypeScript.csproj	Source-links the new shared generator into the TypeScript codegen assembly.
src/Aspire.Cli/Templating/CliTemplateFactory.cs	Replaces local/random port-range logic with the shared port generator for CLI templates.
src/Aspire.Cli/Commands/InitCommand.cs	Uses the shared generator when writing default profiles during thin aspire init.
src/Aspire.Cli/Aspire.Cli.csproj	Source-links the new shared generator into the CLI assembly.

[github-actions]

🚀 Dogfood this PR with:

⚠️ WARNING: Do not do this without first carefully reviewing the code of this PR to satisfy yourself it is safe.

curl -fsSL https://raw.githubusercontent.com/microsoft/aspire/main/eng/scripts/get-aspire-cli-pr.sh | bash -s -- 16629

Or

• Run remotely in PowerShell:

iex "& { $(irm https://raw.githubusercontent.com/microsoft/aspire/main/eng/scripts/get-aspire-cli-pr.ps1) } 16629"

[Eric Erhardt (eerhardt)]

/backport to release/13.3

[github-actions]

Started backporting to release/13.3 (link to workflow run)