feat: Add integration test suite for Position Manager

- Added Jest + ts-jest configuration (jest.config.js)
- Added global test setup with mocks (tests/setup.ts)
- Added trade factory helpers (tests/helpers/trade-factory.ts)
- Added 7 test suites covering Position Manager logic:
  - tp1-detection.test.ts (13 tests)
  - breakeven-sl.test.ts (9 tests)
  - adx-runner-sl.test.ts (18 tests)
  - trailing-stop.test.ts (14 tests)
  - edge-cases.test.ts (18 tests)
  - price-verification.test.ts (13 tests)
  - decision-helpers.test.ts (28 tests)
- Added test documentation (tests/README.md)
- Updated package.json with Jest dependencies and scripts
- All 113 tests pass

Co-authored-by: mindesbunister <32161838+mindesbunister@users.noreply.github.com>

package.json

@@ -7,7 +7,11 @@
     "dev": "next dev",
     "build": "next build",
     "start": "next start",
-    "lint": "next lint"
+    "lint": "next lint",
+    "test": "jest",
+    "test:watch": "jest --watch",
+    "test:coverage": "jest --coverage",
+    "test:ci": "jest --ci --coverage --reporters=default --reporters=jest-junit"
   },
   "dependencies": {
     "@drift-labs/sdk": "^2.75.0",
@@ -30,9 +34,13 @@
   },
   "devDependencies": {
     "@types/bn.js": "^5.2.0",
+    "@types/jest": "^29.5.14",
     "@types/node": "^20.11.0",
     "@types/react": "^18.2.0",
     "@types/react-dom": "^18.2.0",
+    "jest": "^29.7.0",
+    "jest-junit": "^16.0.0",
+    "ts-jest": "^29.2.5",
     "ts-node": "^10.9.2",
     "typescript": "^5.3.0"
   },