test: Added sandboxed, isolated Chromium first-run coverage with stat...

- package.json
- package-lock.json
- .gitignore
- playwright.config.ts
- e2e/fixtures.ts
- e2e/smoke.spec.ts
- tests/svg-image.test.tsx

GSD context:
- Milestone: M001 - Merge upstream v0.4.0 into the Gitea fork
- Slice: S02 - Verify combined application behavior
- Task: T01 - Added sandboxed, isolated Chromium first-run coverage with stateful synthetic API fixtures and fail-closed network boundaries.

GSD-Task: S02/T01

playwright.config.ts

@@ -0,0 +1,45 @@
+import { randomUUID } from "node:crypto";
+import path from "node:path";
+import { defineConfig, devices } from "@playwright/test";
+
+// The worker inherits this exact run path; never touch the default auth/data.
+const runDir = process.env.LH_E2E_RUN_DIR ?? path.resolve(".playwright-data", `run-${randomUUID()}`);
+if (path.dirname(runDir) !== path.resolve(".playwright-data") || !/^run-[a-f0-9-]{36}$/.test(path.basename(runDir))) {
+	throw new Error("Unsafe Playwright data directory; expected a fixture-owned UUID path under .playwright-data.");
+}
+process.env.LH_E2E_RUN_DIR = runDir;
+
+export default defineConfig({
+	testDir: "./e2e",
+	fullyParallel: false,
+	workers: 1,
+	retries: 0,
+	timeout: 60_000,
+	expect: { timeout: 15_000 },
+	globalSetup: "./e2e/fixtures.ts",
+	outputDir: "test-results",
+	reporter: [["list"], ["html", { open: "never" }]],
+	use: {
+		baseURL: "http://127.0.0.1:3005",
+		trace: "retain-on-failure",
+		screenshot: "only-on-failure",
+		serviceWorkers: "block",
+		locale: "en-US",
+		launchOptions: { chromiumSandbox: true },
+	},
+	projects: [{ name: "chromium", use: { ...devices["Desktop Chrome"] } }],
+	webServer: {
+		command: "npm run dev -- --hostname 127.0.0.1 --port 3005",
+		url: "http://127.0.0.1:3005",
+		reuseExistingServer: false,
+		timeout: 120_000,
+		stdout: "pipe",
+		stderr: "pipe",
+		env: {
+			LH_IGNORE_ENV_KEYS: "1",
+			LH_DATA_DIR: path.join(runDir, "data"),
+			LH_AUTH_FILE: path.join(runDir, "auth.json"),
+			NEXT_TELEMETRY_DISABLED: "1",
+		},
+	},
+});