feat(soak): scaffold tests/soak package

Placeholder runner, tsconfig with @bot alias to tests/e2e/bot,
gitignored .env.stresstest + artifacts. Real behavior follows
in Task 10 onward.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

tests/soak/README.md

@@ -0,0 +1,21 @@
+# Golf Soak & UX Test Harness
+
+Runs 16 authenticated browser sessions across 4 rooms to populate
+staging scoreboards and stress-test multiplayer stability.
+
+**Spec:** `docs/superpowers/specs/2026-04-10-multiplayer-soak-test-design.md`
+**Bring-up:** `docs/soak-harness-bringup.md`
+
+## Quick start
+
+```bash
+cd tests/soak
+bun install
+bun run seed                                  # first run only
+TEST_URL=http://localhost:8000 bun run smoke
+```
+
+(The scripts also work with `npm run`, `pnpm run`, etc. — bun is what's installed
+on this dev machine.)
+
+Full documentation arrives with Task 31.