test(coverage): bootstrap vitest unit infra and add tests at 90%+ per file (#1245) (#1269)

* test(coverage): bootstrap vitest unit infra and add tests at 90%+ per file (#1245)

Establishes the unit-test runtime AGENTS.md mandates: a vitest "unit"
project alongside the existing storybook project, RTL + jest-dom +
happy-dom, a Mantine-aware render helper, and a 90%-line per-file
coverage gate enforced by CI. Adds 66 test files covering all 62
components under elements/groups/screens/views, plus core/mcp and
clients/web/src/utils. Total: 577 tests, 98.7% line coverage globally.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

* test(coverage): address PR #1269 review feedback

- AGENTS.md: correct coverage gate description (lines ≥ 90, statements ≥ 85,
  functions ≥ 80, branches ≥ 50) with rationale for the relaxed branch
  threshold
- InspectorView.test.tsx: document what the Math.random() mock values
  (0.1 / 0.99) control vs. STUB_SUCCESS_RATE in InspectorView.tsx
- vite.config.ts / tsconfig.test.json: drop unused `globals: true` and the
  `vitest/globals` type now that every test file imports describe/it/expect/vi
  explicitly; manual `afterEach(cleanup)` in setup.ts remains required because
  testing-library auto-cleanup relies on globalThis.afterEach

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

clients/web/src/components/groups/PromptArgumentsForm/PromptArgumentsForm.test.tsx

@@ -0,0 +1,146 @@
+import { describe, it, expect, vi } from "vitest";
+import userEvent from "@testing-library/user-event";
+import type { Prompt } from "@modelcontextprotocol/sdk/types.js";
+import { renderWithMantine, screen } from "../../../test/renderWithMantine";
+import { PromptArgumentsForm } from "./PromptArgumentsForm";
+
+const promptNoArgs: Prompt = {
+  name: "summarize",
+  description: "Summarize the given text into key points",
+};
+
+const promptWithArgs: Prompt = {
+  name: "translate",
+  title: "Translate Text",
+  description: "Translate text from one language to another",
+  arguments: [
+    { name: "text", required: true, description: "The text to translate" },
+    {
+      name: "targetLanguage",
+      required: false,
+      description: "The language to translate into",
+    },
+  ],
+};
+
+const promptNoDescription: Prompt = {
+  name: "code-review",
+  arguments: [
+    { name: "code", required: true, description: "The code to review" },
+  ],
+};
+
+describe("PromptArgumentsForm", () => {
+  it("renders the prompt name when title is missing", () => {
+    renderWithMantine(
+      <PromptArgumentsForm
+        prompt={promptNoArgs}
+        argumentValues={{}}
+        onArgumentChange={vi.fn()}
+        onGetPrompt={vi.fn()}
+      />,
+    );
+    expect(screen.getByText("summarize")).toBeInTheDocument();
+    expect(
+      screen.getByText("Summarize the given text into key points"),
+    ).toBeInTheDocument();
+  });
+
+  it("prefers the prompt title over the name", () => {
+    renderWithMantine(
+      <PromptArgumentsForm
+        prompt={promptWithArgs}
+        argumentValues={{}}
+        onArgumentChange={vi.fn()}
+        onGetPrompt={vi.fn()}
+      />,
+    );
+    expect(screen.getByText("Translate Text")).toBeInTheDocument();
+  });
+
+  it("does not render Arguments section when prompt has no arguments", () => {
+    renderWithMantine(
+      <PromptArgumentsForm
+        prompt={promptNoArgs}
+        argumentValues={{}}
+        onArgumentChange={vi.fn()}
+        onGetPrompt={vi.fn()}
+      />,
+    );
+    expect(screen.queryByText("Arguments")).not.toBeInTheDocument();
+  });
+
+  it("renders argument inputs and the Arguments title when arguments are present", () => {
+    renderWithMantine(
+      <PromptArgumentsForm
+        prompt={promptWithArgs}
+        argumentValues={{}}
+        onArgumentChange={vi.fn()}
+        onGetPrompt={vi.fn()}
+      />,
+    );
+    expect(screen.getByText("Arguments")).toBeInTheDocument();
+    expect(screen.getByLabelText(/text/)).toBeInTheDocument();
+    expect(screen.getByLabelText(/targetLanguage/)).toBeInTheDocument();
+    expect(screen.getByPlaceholderText("Enter text...")).toBeInTheDocument();
+    expect(
+      screen.getByPlaceholderText("Enter targetLanguage..."),
+    ).toBeInTheDocument();
+  });
+
+  it("renders pre-filled argument values", () => {
+    renderWithMantine(
+      <PromptArgumentsForm
+        prompt={promptWithArgs}
+        argumentValues={{ text: "Hello", targetLanguage: "Spanish" }}
+        onArgumentChange={vi.fn()}
+        onGetPrompt={vi.fn()}
+      />,
+    );
+    expect(screen.getByDisplayValue("Hello")).toBeInTheDocument();
+    expect(screen.getByDisplayValue("Spanish")).toBeInTheDocument();
+  });
+
+  it("invokes onArgumentChange when typing in an argument input", async () => {
+    const user = userEvent.setup();
+    const onArgumentChange = vi.fn();
+    renderWithMantine(
+      <PromptArgumentsForm
+        prompt={promptWithArgs}
+        argumentValues={{}}
+        onArgumentChange={onArgumentChange}
+        onGetPrompt={vi.fn()}
+      />,
+    );
+    await user.type(screen.getByPlaceholderText("Enter text..."), "h");
+    expect(onArgumentChange).toHaveBeenCalledWith("text", "h");
+  });
+
+  it("invokes onGetPrompt when Get Prompt is clicked", async () => {
+    const user = userEvent.setup();
+    const onGetPrompt = vi.fn();
+    renderWithMantine(
+      <PromptArgumentsForm
+        prompt={promptWithArgs}
+        argumentValues={{}}
+        onArgumentChange={vi.fn()}
+        onGetPrompt={onGetPrompt}
+      />,
+    );
+    await user.click(screen.getByRole("button", { name: "Get Prompt" }));
+    expect(onGetPrompt).toHaveBeenCalledTimes(1);
+  });
+
+  it("renders without description when none is provided", () => {
+    renderWithMantine(
+      <PromptArgumentsForm
+        prompt={promptNoDescription}
+        argumentValues={{}}
+        onArgumentChange={vi.fn()}
+        onGetPrompt={vi.fn()}
+      />,
+    );
+    expect(screen.getByText("code-review")).toBeInTheDocument();
+    expect(screen.getByText("Arguments")).toBeInTheDocument();
+  });
+});