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/screens/LoggingScreen/LoggingScreen.test.tsx

@@ -0,0 +1,100 @@
+import { describe, it, expect, vi } from "vitest";
+import userEvent from "@testing-library/user-event";
+import { renderWithMantine, screen } from "../../../test/renderWithMantine";
+import { LoggingScreen } from "./LoggingScreen";
+
+const baseProps = {
+  entries: [],
+  currentLevel: "info" as const,
+  onSetLevel: vi.fn(),
+  onClear: vi.fn(),
+  onExport: vi.fn(),
+  autoScroll: true,
+  onToggleAutoScroll: vi.fn(),
+  onCopyAll: vi.fn(),
+};
+
+describe("LoggingScreen", () => {
+  it("renders the log stream panel", () => {
+    renderWithMantine(<LoggingScreen {...baseProps} />);
+    expect(screen.getByText("Log Stream")).toBeInTheDocument();
+    expect(screen.getByText("No log entries")).toBeInTheDocument();
+  });
+
+  it("renders log entries", () => {
+    const entries = [
+      {
+        receivedAt: new Date(),
+        params: { level: "info" as const, data: "hello" },
+      },
+    ];
+    renderWithMantine(<LoggingScreen {...baseProps} entries={entries} />);
+    expect(screen.getByText("hello")).toBeInTheDocument();
+  });
+
+  it("invokes onClear when clear is clicked", async () => {
+    const user = userEvent.setup();
+    const onClear = vi.fn();
+    renderWithMantine(<LoggingScreen {...baseProps} onClear={onClear} />);
+    await user.click(screen.getByRole("button", { name: "Clear" }));
+    expect(onClear).toHaveBeenCalledTimes(1);
+  });
+
+  it("invokes onCopyAll when Copy All is clicked", async () => {
+    const user = userEvent.setup();
+    const onCopyAll = vi.fn();
+    renderWithMantine(<LoggingScreen {...baseProps} onCopyAll={onCopyAll} />);
+    await user.click(screen.getByRole("button", { name: "Copy All" }));
+    expect(onCopyAll).toHaveBeenCalledTimes(1);
+  });
+
+  it("toggles a single level on level button click", async () => {
+    const user = userEvent.setup();
+    const entries = [
+      { receivedAt: new Date(), params: { level: "info" as const, data: "x" } },
+    ];
+    renderWithMantine(<LoggingScreen {...baseProps} entries={entries} />);
+    expect(screen.getByText("x")).toBeInTheDocument();
+    const debugButton = screen.getByRole("button", { name: "info" });
+    await user.click(debugButton);
+    expect(screen.queryByText("x")).not.toBeInTheDocument();
+  });
+
+  it("Deselect All hides all entries; Select All restores them", async () => {
+    const user = userEvent.setup();
+    const entries = [
+      { receivedAt: new Date(), params: { level: "info" as const, data: "x" } },
+    ];
+    renderWithMantine(<LoggingScreen {...baseProps} entries={entries} />);
+    await user.click(screen.getByRole("button", { name: "Deselect All" }));
+    expect(screen.queryByText("x")).not.toBeInTheDocument();
+    await user.click(screen.getByRole("button", { name: "Select All" }));
+    expect(screen.getByText("x")).toBeInTheDocument();
+  });
+
+  it("filters log text via the search input", async () => {
+    const user = userEvent.setup();
+    const entries = [
+      {
+        receivedAt: new Date(),
+        params: { level: "info" as const, data: "alpha" },
+      },
+      {
+        receivedAt: new Date(),
+        params: { level: "info" as const, data: "beta" },
+      },
+    ];
+    renderWithMantine(<LoggingScreen {...baseProps} entries={entries} />);
+    await user.type(screen.getByPlaceholderText("Search..."), "alpha");
+    expect(screen.getByText("alpha")).toBeInTheDocument();
+    expect(screen.queryByText("beta")).not.toBeInTheDocument();
+  });
+
+  it("invokes onSetLevel via the Set button", async () => {
+    const user = userEvent.setup();
+    const onSetLevel = vi.fn();
+    renderWithMantine(<LoggingScreen {...baseProps} onSetLevel={onSetLevel} />);
+    await user.click(screen.getByRole("button", { name: "Set" }));
+    expect(onSetLevel).toHaveBeenCalledWith("info");
+  });
+});