Fix AppHost SDK version compatibility check to accept preview versions

[Copilot]

Problem

The AppHostHelper was using SemVersion.ComparePrecedenceTo() to validate Aspire.Hosting package versions, which follows SemVer 2.0.0 precedence rules. According to these rules, prerelease versions have lower precedence than release versions when their major.minor.patch components are equal. This caused preview versions to be incorrectly rejected:

User has: 13.0.0-preview.1.25520.1
Minimum: 13.0.0

Result: REJECTED ❌
Error: "The Aspire.Hosting package version 13.0.0-preview.1.25520.1 is not supported. Please update to the latest version."

The issue manifests when the minimum version matches the major.minor.patch of a preview version being used. While the current code works with minimum version 9.2.0, it would break when updated to match current release versions (e.g., 13.0.0).

Solution

Replaced ComparePrecedenceTo() with a custom CompareMajorMinorPatch() method that compares only the major, minor, and patch components while ignoring prerelease identifiers and build metadata. This ensures preview versions are accepted as long as their semantic version number (major.minor.patch) meets or exceeds the minimum requirement.

Before:

if (aspireVersion.ComparePrecedenceTo(minimumVersion) < 0)
{
    // Reject - would fail for 13.0.0-preview.1 vs 13.0.0
}

After:

if (CompareMajorMinorPatch(aspireVersion, minimumVersion) < 0)
{
    // Accept preview versions with matching or higher major.minor.patch
}

private static int CompareMajorMinorPatch(SemVersion version, SemVersion other)
{
    if (version.Major != other.Major)
        return version.Major.CompareTo(other.Major);
    if (version.Minor != other.Minor)
        return version.Minor.CompareTo(other.Minor);
    return version.Patch.CompareTo(other.Patch);
}

Testing

Added comprehensive test suite with 21 test cases covering:

• Preview versions with and without build metadata
• Multiple prerelease types (preview, alpha, beta, rc)
• Edge cases (exact matches, patch/minor/major differences)
• Error conditions (invalid versions, non-AppHost projects)

All tests pass:

• New tests: 21/21 ✅
• Existing CLI tests: 511/511 ✅

Impact

• ✅ Users with preview versions can now use the Aspire CLI without compatibility errors
• ✅ Future-proof for when minimum version requirements are updated
• ✅ No breaking changes to existing functionality
• ✅ Minimal code changes (30 lines modified, 173 lines of tests added)

Fixes #[issue-number]

Original prompt

---

This section details on the original issue you should resolve

<issue_title>AppHost SDK incompatability warning when using previews</issue_title>
<issue_description>The AppHostHelper APIs uses a precendence check based on SemVer that results in issues when a package is targeting 13.0.0-preview.*. I'm not sure why this is happening since 13.x.x is greater tha 9.x.x.

aspire/src/Aspire.Cli/Utils/AppHostHelper.cs

Line 39 in 209cf0e

if (aspireVersion.ComparePrecedenceTo(minimumVersion) < 0)

The Aspire.Hosting package version 13.0.0-preview.1.25520.1 is not supported. Please update to the latest version.</issue_description>

Comments on the Issue (you are @copilot in this section)

@davidfowl @mitchdenny I changed this code when we changed the version to 13, not sure why it's broken.

Fixes #12229

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