fix: show custom BYOK models in selector (#1321)

Co-authored-by: Letta Code <noreply@letta.com>
Co-authored-by: cpacker <packercharles@gmail.com>

src/tests/cli/model-selector-byok-custom-provider.test.ts

@@ -0,0 +1,44 @@
+import { describe, expect, test } from "bun:test";
+import {
+  buildByokProviderAliases,
+  isByokHandleForSelector,
+} from "../../cli/components/ModelSelector";
+
+describe("ModelSelector custom BYOK provider detection", () => {
+  test("treats connected custom OpenAI providers as BYOK", () => {
+    const aliases = buildByokProviderAliases([
+      {
+        name: "openai-sarah",
+        provider_type: "openai",
+      },
+    ]);
+
+    expect(aliases["openai-sarah"]).toBe("openai");
+    expect(isByokHandleForSelector("openai-sarah/gpt-5.4-fast", aliases)).toBe(
+      true,
+    );
+  });
+
+  test("maps custom OpenAI provider handles back to base openai handles", () => {
+    const aliases = buildByokProviderAliases([
+      {
+        name: "openai-sarah",
+        provider_type: "openai",
+      },
+    ]);
+
+    const provider = "openai-sarah";
+    const model = "gpt-5.4-fast";
+    const baseProvider = aliases[provider];
+
+    expect(`${baseProvider}/${model}`).toBe("openai/gpt-5.4-fast");
+  });
+
+  test("preserves existing lc-* aliases", () => {
+    const aliases = buildByokProviderAliases([]);
+
+    expect(isByokHandleForSelector("lc-openai/gpt-5.4-fast", aliases)).toBe(
+      true,
+    );
+  });
+});