Drop redundant RuntimeConnection + COPILOT_CLI_PATH from scenarios

Most scenarios explicitly set up a stdio connection from COPILOT_CLI_PATH:

  - .NET:  Connection = RuntimeConnection.ForStdio(path: Environment.GetEnvironmentVariable("COPILOT_CLI_PATH"))
  - TS:    connection: RuntimeConnection.forStdio({ path: process.env.COPILOT_CLI_PATH })

This is redundant boilerplate:

  - The default `RuntimeConnection` is already stdio across every SDK.
  - When no `path` is given, the SDKs already fall back to the
    `COPILOT_CLI_PATH` env var (and then the bundled binary), so the
    explicit pass-through adds nothing.
  - No real consumer of the SDK would write this — the docs reasonably
    expect `new CopilotClient()` (or the language-equivalent) to Just Work.

Drop the connection setup entirely in every scenario *except* those whose
whole purpose is to demonstrate transport / bundling configuration:

  - `transport/stdio` — explicit stdio path is the point.
  - `transport/tcp` / `transport/reconnect` — TCP transport is the point.
  - `bundling/*` — bundled-binary lookup is the point.

Also clean up the resulting cruft:

  - Empty `new CopilotClientOptions {}` / `new CopilotClient({})` literals
    collapsed to parameter-less constructors.
  - Unused `RuntimeConnection` imports stripped from TS scenarios.
  - Go scenarios that previously passed `&copilot.ClientOptions{}` now
    pass `nil` (idiomatic when no fields are set).
  - The `cliPath` local var in `tools/custom-agents` (.NET) deleted.

Rust scenarios keep `ClientOptions::default()` because the API requires
the argument — that's idiomatic Rust, not redundant boilerplate.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: SteveSandersonMS

test/scenarios/auth/byok-anthropic/csharp/Program.cs

@@ -10,10 +10,7 @@
     return 1;
 }
 
-using var client = new CopilotClient(new CopilotClientOptions
-{
-    Connection = RuntimeConnection.ForStdio(path: Environment.GetEnvironmentVariable("COPILOT_CLI_PATH")),
-});
+using var client = new CopilotClient();
 
 await client.StartAsync();
 

test/scenarios/auth/byok-anthropic/go/main.go

@@ -25,7 +25,7 @@ func main() {
 		model = "claude-sonnet-4-20250514"
 	}
 
-	client := copilot.NewClient(&copilot.ClientOptions{})
+	client := copilot.NewClient(nil)
 
 	ctx := context.Background()
 	if err := client.Start(ctx); err != nil {

test/scenarios/auth/byok-anthropic/typescript/src/index.ts

@@ -1,4 +1,4 @@
-import { CopilotClient , RuntimeConnection } from "@github/copilot-sdk";
+import { CopilotClient } from "@github/copilot-sdk";
 
 async function main() {
   const apiKey = process.env.ANTHROPIC_API_KEY;
@@ -9,9 +9,7 @@ async function main() {
     process.exit(1);
   }
 
-  const client = new CopilotClient({
-    connection: RuntimeConnection.forStdio({ path: process.env.COPILOT_CLI_PATH }),
-  });
+  const client = new CopilotClient();
 
   try {
     const session = await client.createSession({

test/scenarios/auth/byok-azure/csharp/Program.cs

@@ -11,10 +11,7 @@
     return 1;
 }
 
-using var client = new CopilotClient(new CopilotClientOptions
-{
-    Connection = RuntimeConnection.ForStdio(path: Environment.GetEnvironmentVariable("COPILOT_CLI_PATH")),
-});
+using var client = new CopilotClient();
 
 await client.StartAsync();
 

test/scenarios/auth/byok-azure/go/main.go

@@ -26,7 +26,7 @@ func main() {
 		apiVersion = "2024-10-21"
 	}
 
-	client := copilot.NewClient(&copilot.ClientOptions{})
+	client := copilot.NewClient(nil)
 
 	ctx := context.Background()
 	if err := client.Start(ctx); err != nil {

test/scenarios/auth/byok-azure/typescript/src/index.ts

@@ -1,4 +1,4 @@
-import { CopilotClient , RuntimeConnection } from "@github/copilot-sdk";
+import { CopilotClient } from "@github/copilot-sdk";
 
 async function main() {
   const endpoint = process.env.AZURE_OPENAI_ENDPOINT;
@@ -10,9 +10,7 @@ async function main() {
     process.exit(1);
   }
 
-  const client = new CopilotClient({
-    connection: RuntimeConnection.forStdio({ path: process.env.COPILOT_CLI_PATH }),
-  });
+  const client = new CopilotClient();
 
   try {
     const session = await client.createSession({

test/scenarios/auth/byok-ollama/csharp/Program.cs

@@ -6,10 +6,7 @@
 var compactSystemPrompt =
     "You are a compact local assistant. Keep answers short, concrete, and under 80 words.";
 
-using var client = new CopilotClient(new CopilotClientOptions
-{
-    Connection = RuntimeConnection.ForStdio(path: Environment.GetEnvironmentVariable("COPILOT_CLI_PATH")),
-});
+using var client = new CopilotClient();
 
 await client.StartAsync();
 

test/scenarios/auth/byok-ollama/go/main.go

@@ -22,7 +22,7 @@ func main() {
 		model = "llama3.2:3b"
 	}
 
-	client := copilot.NewClient(&copilot.ClientOptions{})
+	client := copilot.NewClient(nil)
 
 	ctx := context.Background()
 	if err := client.Start(ctx); err != nil {

test/scenarios/auth/byok-ollama/typescript/src/index.ts

@@ -1,15 +1,14 @@
-import { CopilotClient , RuntimeConnection } from "@github/copilot-sdk";
+import { CopilotClient } from "@github/copilot-sdk";
 
-const OLLAMA_BASE_URL = process.env.OLLAMA_BASE_URL ?? "http://localhost:11434/v1";
+const OLLAMA_BASE_URL =
+  process.env.OLLAMA_BASE_URL ?? "http://localhost:11434/v1";
 const OLLAMA_MODEL = process.env.OLLAMA_MODEL ?? "llama3.2:3b";
 
 const COMPACT_SYSTEM_PROMPT =
   "You are a compact local assistant. Keep answers short, concrete, and under 80 words.";
 
 async function main() {
-  const client = new CopilotClient({
-    connection: RuntimeConnection.forStdio({ path: process.env.COPILOT_CLI_PATH }),
-  });
+  const client = new CopilotClient();
 
   try {
     const session = await client.createSession({

test/scenarios/auth/byok-openai/csharp/Program.cs

@@ -10,10 +10,7 @@
     return 1;
 }
 
-using var client = new CopilotClient(new CopilotClientOptions
-{
-    Connection = RuntimeConnection.ForStdio(path: Environment.GetEnvironmentVariable("COPILOT_CLI_PATH")),
-});
+using var client = new CopilotClient();
 
 await client.StartAsync();