Update Java integration docs for 13.3

[marshalhayes]

Updates the Java integration docs to reflect the current Community Toolkit Java integration APIs introduced in Aspire 13.3, replacing the deprecated AddSpringApp/JavaAppResourceOptions patterns.

Changes

• Replace deprecated AddSpringApp with AddJavaApp, WithMavenGoal, WithGradleTask, etc.
• Add full C# and TypeScript AppHost parity throughout
• Add sections for: build before run, run a container image, pass environment variables, health checks, configure JVM arguments, and configure OpenTelemetry
• Use JdbcConnectionString / UserNameReference / PasswordParameter expressions for Spring Boot datasource configuration (PR #11938)
• Apply code token highlighting throughout
• Follow the same style and structure as the JavaScript and Python integration docs

[marshalhayes]

@microsoft-github-policy-service agree

[Copilot]

Pull request overview

Updates the Java integration documentation to reflect newer Aspire Community Toolkit Java hosting patterns and adds C#/TypeScript AppHost parity, aligning the page structure with other language integration docs.

Changes:

• Replaces deprecated Spring-specific APIs with newer Java app/container APIs and adds Maven/Gradle/JAR guidance.
• Adds C# + TypeScript tabbed samples throughout using the synced aspire-lang selector.
• Expands coverage with sections for building before run, env var injection (including JDBC expressions), health checks, JVM args, and OpenTelemetry agent setup.

Comments suppressed due to low confidence (2)

src/frontend/src/content/docs/integrations/frameworks/java.mdx:73

• The Gradle examples reference WithGradleTask(...) / WithGradleBuild(...), but these APIs don’t exist in the currently vendored CommunityToolkit.Aspire.Hosting.Java metadata (13.1.1). Either vendor the newer package metadata that adds Gradle support, or rewrite this section against the available API surface to avoid publishing non-compilable examples.

### Run with Gradle

<Tabs syncKey='aspire-lang'>
<TabItem id='csharp' label='C#'>

```csharp title="C# — AppHost.cs" "WithGradleTask"
var builder = DistributedApplication.CreateBuilder(args);

var javaApp = builder.AddJavaApp("spring-api", "../spring-app")
    .WithGradleTask("bootRun")
    .WithHttpEndpoint(env: "SERVER_PORT");

src/frontend/src/content/docs/integrations/frameworks/java.mdx:226

• This section introduces AddJavaContainerApp(...) and later WithOtelAgent(...), but those members are not present in the repo’s current CommunityToolkit.Aspire.Hosting.Java API metadata (13.1.1, where container hosting is via AddJavaApp(..., JavaAppContainerResourceOptions) and OTEL agent config is via options). Please align the docs with the vendored API version or update the vendored metadata to the intended 13.3 API so the doc tooling and readers aren’t pointed at missing members.

### Run a container image

<Tabs syncKey='aspire-lang'>
<TabItem id='csharp' label='C#'>

```csharp title="C# — AppHost.cs"
var builder = DistributedApplication.CreateBuilder(args);

var javaApp = builder.AddJavaContainerApp(
    name: "java-api",
    image: "docker.io/example/spring-api",
    imageTag: "latest")
    .WithHttpEndpoint(env: "SERVER_PORT");

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[IEvangelist]

Did the support for TS in the Community Toolkit ship? I didn't think that happened yet. We'd need to remove the TS tabs as they're not yet supported.

[marshalhayes]

I thought the polyglot support shipped with 13.3 last week