Add Copilot SDK Java instructions file

[brunoborges]

Adds instructions/copilot-sdk-java.instructions.md — a comprehensive guide for building Java applications with the Copilot SDK.

Modeled after the C# equivalent at github/awesome-copilot, adapted to Java idioms:

• Client initialization with CopilotClient and CopilotClientOptions
• Session management including create, resume, list, delete
• Event handling with typed on() subscriptions and pattern matching
• Streaming with delta and final event handling
• Custom tools via ToolDefinition.create() with type-safe argument deserialization
• Permission & user input handlers
• System message customization (append/replace modes)
• BYOK provider configuration (OpenAI, Azure)
• Common patterns — query-response, multi-turn, session hooks
• Best practices — try-with-resources, CompletableFuture usage, error handling

The frontmatter applyTo targets **.java and **/pom.xml files.

[Copilot]

Pull request overview

Adds a new Copilot instruction file intended to guide Java developers in using copilot-sdk-java, covering client/session setup, event handling, streaming, tools, hooks, and BYOK provider configuration.

Changes:

• Introduces instructions/copilot-sdk-java.instructions.md with end-to-end usage patterns for the SDK.
• Documents key SDK APIs (client options, session config, events, tools, permissions, user input, etc.).
• Includes copy/paste code samples for common workflows (streaming, tools, hooks, BYOK).

Comments suppressed due to low confidence (5)

instructions/copilot-sdk-java.instructions.md:31

• Gradle example uses the wrong groupId (com.github.copilot). It should match the published coordinates used by this project (groupId com.github, artifactId copilot-sdk-java).

```groovy
implementation 'com.github.copilot:copilot-sdk-java:LATEST'

**instructions/copilot-sdk-java.instructions.md:760**
* `SessionHooks.setOnPostToolUse(...)` also takes `(input, invocation)` and returns `CompletableFuture<PostToolUseHookOutput>` (nullable). The one-parameter lambda in this snippet won’t compile; update it to match the handler signature.

    .setOnPostToolUse(hook -> {
        System.out.println("Tool execution complete: " + hook);
        return CompletableFuture.completedFuture(null);
    }))

**instructions/copilot-sdk-java.instructions.md:242**
* `setEventErrorHandler` expects an `EventErrorHandler` with signature `(event, exception) -> { ... }`, not a single-parameter lambda. Update the sample to accept both the event being dispatched and the thrown exception.

// Set a custom error handler
session.setEventErrorHandler(ex -> {
logger.error("Event handler error", ex);
});

**instructions/copilot-sdk-java.instructions.md:394**
* The permission result kind string in this example ("user-denied") doesn’t match the well-known kinds used elsewhere in this SDK/tests (e.g., "denied-interactively-by-user" or `PermissionRequestResultKind.DENIED_INTERACTIVELY_BY_USER`). Using the well-known values (or the `PermissionRequestResultKind` constants) avoids interoperability issues with the CLI.

    if ("dangerous-action".equals(request.getKind())) {
        return CompletableFuture.completedFuture(
            new PermissionRequestResult().setKind("user-denied")
        );
    }

**instructions/copilot-sdk-java.instructions.md:531**
* This Azure BYOK example won’t compile against the current SDK: `AzureOptions` only supports `setApiVersion(...)`, and the tested provider type is `"azure-openai"` with `ProviderConfig.setBaseUrl(...)` + `setApiKey(...)` (see `ProviderConfigTest`). Please update the snippet to match the actual `ProviderConfig`/`AzureOptions` API so users can copy/paste it successfully.

var session = client.createSession(new SessionConfig()
.setProvider(new ProviderConfig()
.setType("azure")
.setAzure(new AzureOptions()
.setEndpoint("https://my-resource.openai.azure.com")
.setDeployment("gpt-4"))

</details>



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