fix(tui): restore custom provider in /connect (#26168)

packages/opencode/test/cli/cmd/tui/provider-options.test.ts

@@ -0,0 +1,29 @@
+import { describe, expect, test } from "bun:test"
+import { normalizeCustomProviderID, providerOptions } from "../../../../src/cli/cmd/tui/component/dialog-provider"
+
+describe("providerOptions", () => {
+  test("includes a synthetic Other option for custom providers", () => {
+    expect(providerOptions([{ id: "openai", name: "OpenAI" }]).at(-1)).toMatchObject({
+      title: "Other",
+      description: "Custom provider",
+      category: "Providers",
+    })
+  })
+
+  test("does not use Other as the generic provider category", () => {
+    expect(providerOptions([{ id: "mistral", name: "Mistral" }])[0]?.category).toBe("Providers")
+  })
+
+  test("does not collide with a configured provider named other", () => {
+    const values = providerOptions([{ id: "other", name: "Other Provider" }]).map((option) => option.value)
+    expect(new Set(values).size).toBe(values.length)
+  })
+
+  test("normalizes and validates custom provider ids", () => {
+    expect(normalizeCustomProviderID("  custom-provider  ")).toBe("custom-provider")
+    expect(normalizeCustomProviderID("custom_provider")).toBe("custom_provider")
+    expect(normalizeCustomProviderID("@ai-sdk/custom-provider")).toBe("custom-provider")
+    expect(normalizeCustomProviderID("-custom-provider")).toBeUndefined()
+    expect(normalizeCustomProviderID("Custom Provider")).toBeUndefined()
+  })
+})