Add spin session functionality and update game mechanics

- Introduced a new `spin_sessions` table to track user spin activities.
- Updated the API to include a new endpoint for spinning games, allowing users to place bets and specify spin counts.
- Enhanced game information structure and added validation for bets and spin counts.
- Implemented the `Forest Fortune` slot game mechanics, including payline evaluation and scatter functionality.
- Updated dependencies in `pyproject.toml` for development and added `httpx` for HTTP requests.
- Added unit tests for the new slot mechanics and API endpoints to ensure functionality and reliability.

app/slots/rng.py

@@ -0,0 +1,24 @@
+from __future__ import annotations
+
+import random
+from typing import Any, Protocol, Sequence
+
+
+class Rng(Protocol):
+    def random(self) -> float: ...
+
+    def choices(
+        self,
+        population: Sequence[Any],
+        weights: Sequence[float] | None = None,
+        *,
+        k: int = 1,
+    ) -> list[Any]: ...
+
+
+def system_rng() -> random.SystemRandom:
+    return random.SystemRandom()
+
+
+def seeded_rng(seed: int | str | bytes | bytearray) -> random.Random:
+    return random.Random(seed)