fix(claude-code-cli): resolve SDK executable path and update model IDs

- Add pathToClaudeCodeExecutable to SDK query options, resolving the
  system `claude` binary via `which claude`. Without this, the SDK
  looks for a bundled cli.js that doesn't exist when installed as a
  library dependency.
- Remove env option that was replacing the subprocess environment and
  stripping auth credentials, causing "Not logged in" errors.
- Update model IDs to current versions: claude-opus-4-6 (1M ctx),
  claude-sonnet-4-6 (1M ctx), claude-haiku-4-5 (200K ctx).

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/resources/extensions/claude-code-cli/models.ts

@@ -4,36 +4,39 @@
  * Costs are zero because inference is covered by the user's Claude Code
  * subscription. The SDK's `result` message still provides token counts
  * for display in the TUI.
+ *
+ * Context windows and max tokens match the Anthropic API definitions
+ * in models.generated.ts.
  */
 
 const ZERO_COST = { input: 0, output: 0, cacheRead: 0, cacheWrite: 0 };
 
 export const CLAUDE_CODE_MODELS = [
 	{
-		id: "claude-opus-4-20250514",
-		name: "Claude Opus 4 (via Claude Code)",
+		id: "claude-opus-4-6",
+		name: "Claude Opus 4.6 (via Claude Code)",
 		reasoning: true,
 		input: ["text", "image"] as ("text" | "image")[],
 		cost: ZERO_COST,
-		contextWindow: 200_000,
-		maxTokens: 32_768,
+		contextWindow: 1_000_000,
+		maxTokens: 128_000,
 	},
 	{
-		id: "claude-sonnet-4-20250514",
-		name: "Claude Sonnet 4 (via Claude Code)",
+		id: "claude-sonnet-4-6",
+		name: "Claude Sonnet 4.6 (via Claude Code)",
 		reasoning: true,
 		input: ["text", "image"] as ("text" | "image")[],
 		cost: ZERO_COST,
-		contextWindow: 200_000,
-		maxTokens: 16_384,
+		contextWindow: 1_000_000,
+		maxTokens: 64_000,
 	},
 	{
-		id: "claude-haiku-4-5-20251001",
+		id: "claude-haiku-4-5",
 		name: "Claude Haiku 4.5 (via Claude Code)",
-		reasoning: false,
+		reasoning: true,
 		input: ["text", "image"] as ("text" | "image")[],
 		cost: ZERO_COST,
 		contextWindow: 200_000,
-		maxTokens: 8_192,
+		maxTokens: 64_000,
 	},
 ];

src/resources/extensions/claude-code-cli/stream-adapter.ts

@@ -16,6 +16,7 @@ import type {
 	SimpleStreamOptions,
 } from "@gsd/pi-ai";
 import { EventStream } from "@gsd/pi-ai";
+import { execSync } from "node:child_process";
 import { PartialMessageBuilder, ZERO_USAGE, mapUsage } from "./partial-builder.js";
 import type {
 	SDKAssistantMessage,
@@ -46,6 +47,29 @@ function createAssistantStream(): AssistantMessageEventStream {
 	) as AssistantMessageEventStream;
 }
 
+// ---------------------------------------------------------------------------
+// Claude binary resolution
+// ---------------------------------------------------------------------------
+
+let cachedClaudePath: string | null = null;
+
+/**
+ * Resolve the path to the system-installed `claude` binary.
+ * The SDK defaults to a bundled cli.js which doesn't exist when
+ * installed as a library — we need to point it at the real CLI.
+ */
+function getClaudePath(): string {
+	if (cachedClaudePath) return cachedClaudePath;
+	try {
+		cachedClaudePath = execSync("which claude", { timeout: 5_000, stdio: "pipe" })
+			.toString()
+			.trim();
+	} catch {
+		cachedClaudePath = "claude"; // fall back to PATH resolution
+	}
+	return cachedClaudePath;
+}
+
 // ---------------------------------------------------------------------------
 // Prompt extraction
 // ---------------------------------------------------------------------------
@@ -145,6 +169,7 @@ async function pumpSdkMessages(
 		const queryResult = sdk.query({
 			prompt,
 			options: {
+				pathToClaudeCodeExecutable: getClaudePath(),
 				model: modelId,
 				includePartialMessages: true,
 				persistSession: false,
@@ -154,7 +179,6 @@ async function pumpSdkMessages(
 				allowDangerouslySkipPermissions: true,
 				settingSources: ["project"],
 				systemPrompt: { type: "preset", preset: "claude_code" },
-				env: { CLAUDE_AGENT_SDK_CLIENT_APP: "gsd" },
 				betas: modelId.includes("sonnet") ? ["context-1m-2025-08-07"] : [],
 			},
 		});