test: exclude screenshot-gen from default E2E run; wire pdf-server tests

Bug 1: generate-grid-screenshots.spec.ts was running on every CI E2E
invocation because playwright.config.ts had no testIgnore. This spec
writes examples/*/grid-cell.png as a side effect — it's meant to be
invoked only via npm run generate:screenshots.

Added testIgnore gated on GENERATE_SCREENSHOTS env var (Playwright's
testIgnore is stronger than explicit CLI file args, so a plain ignore
would break generate:screenshots). Passed the env var through the
docker invocation in generate:screenshots.

  Before: npx playwright test --list → 82 tests in 3 files
  After:  npx playwright test --list → 65 tests in 2 files
  GENERATE_SCREENSHOTS=1 ... --list → 17 tests in 1 file (still works)

Bug 2: examples/pdf-server/server.test.ts (448 LOC, 34 tests) was
never run — root script was 'bun test src'. Changed to 'bun test src
examples'. Only one .test. file exists in examples/ so no noise.

  Before: npm test → 87 pass across 3 files
  After:  npm test → 121 pass across 4 files

Author: ochafik

package.json

@@ -50,7 +50,7 @@
     "build": "npm run generate:schemas && npm run sync:snippets && node scripts/run-bun.mjs build.bun.ts && node scripts/link-self.mjs",
     "prepack": "npm run build",
     "build:all": "npm run examples:build",
-    "test": "bun test src",
+    "test": "bun test src examples",
     "test:e2e": "playwright test",
     "test:e2e:update": "playwright test --update-snapshots",
     "test:e2e:ui": "playwright test --ui",
@@ -64,7 +64,7 @@
     "prepare": "npm run build && husky",
     "docs": "typedoc",
     "docs:watch": "typedoc --watch",
-    "generate:screenshots": "npm run build:all && docker run --rm -e EXAMPLE -v $(pwd):/work -w /work mcr.microsoft.com/playwright:v1.57.0-noble sh -c 'apt-get update -qq && apt-get install -qq -y python3-venv curl > /dev/null && curl -LsSf https://astral.sh/uv/install.sh | sh && export PATH=\"$HOME/.local/bin:$PATH\" && npm i -g bun && npm ci && npx playwright test tests/e2e/generate-grid-screenshots.spec.ts'",
+    "generate:screenshots": "npm run build:all && docker run --rm -e EXAMPLE -e GENERATE_SCREENSHOTS=1 -v $(pwd):/work -w /work mcr.microsoft.com/playwright:v1.57.0-noble sh -c 'apt-get update -qq && apt-get install -qq -y python3-venv curl > /dev/null && curl -LsSf https://astral.sh/uv/install.sh | sh && export PATH=\"$HOME/.local/bin:$PATH\" && npm i -g bun && npm ci && npx playwright test tests/e2e/generate-grid-screenshots.spec.ts'",
     "prettier": "prettier -u \"**/*.{js,jsx,ts,tsx,mjs,json,md,yml,yaml}\" --check",
     "prettier:fix": "prettier -u \"**/*.{js,jsx,ts,tsx,mjs,json,md,yml,yaml}\" --write",
     "check:versions": "node scripts/check-versions.mjs",

playwright.config.ts

@@ -2,6 +2,13 @@ import { defineConfig, devices } from "@playwright/test";
 
 export default defineConfig({
   testDir: "./tests/e2e",
+  // Exclude the screenshot generation spec from default runs.
+  // It writes examples/*/grid-cell.png as a side effect and is meant to be
+  // invoked only via `npm run generate:screenshots` (which sets
+  // GENERATE_SCREENSHOTS=1 to bypass this ignore).
+  testIgnore: process.env.GENERATE_SCREENSHOTS
+    ? []
+    : ["**/generate-grid-screenshots.spec.ts"],
   fullyParallel: true,
   forbidOnly: !!process.env.CI,
   retries: process.env.CI ? 2 : 0,