Use seedrandom to back PseudoRandom.ts (#1828)

## Description:

The previous implementation had a bug that biased numbers away from 0,
so random.chance(1500+) would always return false. This caused trains to
not spawn at all when their spawn rate was sufficiently low. We should
be using a library instead of implementing it from scratch anyways.

## Please complete the following:

- [x] I have added screenshots for all UI updates
- [x] I process any text displayed to the user through translateText()
and I've added it to the en.json file
- [x] I have added relevant tests to the test directory
- [x] I confirm I have thoroughly tested these changes and take full
responsibility for any bugs introduced

## Please put your Discord username so you can be contacted if a bug or
regression is found:

evan

package.json

@@ -41,6 +41,7 @@
     "@types/msgpack5": "^3.4.6",
     "@types/node": "^22.10.2",
     "@types/pg": "^8.11.11",
+    "@types/seedrandom": "^3.0.8",
     "@types/sinon": "^17.0.3",
     "@types/systeminformation": "^3.23.1",
     "@types/ws": "^8.5.11",
@@ -118,6 +119,7 @@
     "js-yaml": "^4.1.0",
     "nanoid": "^3.3.6",
     "obscenity": "^0.4.3",
+    "seedrandom": "^3.0.5",
     "ts-node": "^10.9.2",
     "uuid": "^11.1.0",
     "winston": "^3.17.0",