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/elements/LogEntry/LogEntry.test.tsx

@@ -0,0 +1,39 @@
+import { describe, it, expect } from "vitest";
+import { renderWithMantine, screen } from "../../../test/renderWithMantine";
+import { LogEntry, type LogEntryData } from "./LogEntry";
+
+const baseEntry = (
+  overrides: Partial<LogEntryData["params"]>,
+): LogEntryData => ({
+  receivedAt: new Date("2024-01-01T00:00:00Z"),
+  params: { level: "info", data: "hello", ...overrides },
+});
+
+describe("LogEntry", () => {
+  it("renders the message text", () => {
+    renderWithMantine(<LogEntry entry={baseEntry({ data: "the message" })} />);
+    expect(screen.getByText("the message")).toBeInTheDocument();
+  });
+
+  it("renders the level badge", () => {
+    renderWithMantine(<LogEntry entry={baseEntry({ level: "error" })} />);
+    expect(screen.getByText("error")).toBeInTheDocument();
+  });
+
+  it("renders the logger name when present", () => {
+    renderWithMantine(<LogEntry entry={baseEntry({ logger: "transport" })} />);
+    expect(screen.getByText("[transport]")).toBeInTheDocument();
+  });
+
+  it("formats object data as JSON", () => {
+    renderWithMantine(<LogEntry entry={baseEntry({ data: { code: 42 } })} />);
+    expect(screen.getByText('{"code":42}')).toBeInTheDocument();
+  });
+
+  it("renders empty string for null data", () => {
+    const { container } = renderWithMantine(
+      <LogEntry entry={baseEntry({ data: null })} />,
+    );
+    expect(container.textContent).toContain("info");
+  });
+});