[3pts] Implement SqliteGameRepository

[github-actions]

Description

Implement IGameRepository interface using SQLite database for persistence.

Depends on: IGameRepository interface issue

SqliteGameRepository Class

Implements IGameRepository using Microsoft.Data.Sqlite

Database Operations

SaveGame(GameState state)

• Upserts game save by player name
• Creates tables if they don't exist

LoadGame(string playerName)

• Returns GameState if found
• Returns null if not found

SaveScore(string playerName, int score)

• Inserts new leaderboard entry
• Includes timestamp

GetLeaderboard()

• Returns top 10 scores
• Ordered by score descending
• Includes player name, score, and date

Requirements

• Creates database and tables on first run
• Use 'using' statements for connection disposal
• Proper SQL parameterization to prevent injection
• Database file: classcrawler.db

Acceptance Criteria

• SqliteGameRepository class implements IGameRepository
• Uses Microsoft.Data.Sqlite package
• Creates database and tables on first run
• SaveGame(GameState) upserts by player name
• LoadGame(string playerName) returns GameState or null
• SaveScore(string playerName, int score) inserts with timestamp
• GetLeaderboard() returns top 10 scores descending
• Uses 'using' statements for proper disposal
• SQL uses parameters (no injection vulnerabilities)
• Class documented with XML comments