[2pts] Write unit tests — combat system

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Description

Create comprehensive unit tests for combat system components.

Depends on: ICombatStrategy and CombatEngine issues

Test Coverage

ICombatStrategy Tests

• Test each strategy (Melee, Magic, Ranged)
• Verify damage calculation formulas
• Test with various attack and defense values
• Test edge cases

CombatEngine Tests

• Test RunCombat() method
• Player wins scenario
• Enemy wins scenario
• Verify correct XP returned
• Verify correct Gold returned
• Test turn order (player attacks first)

Edge Cases to Cover

• Zero health
• Maximum defense (damage reduction)
• Zero attack power
• Negative values (should not occur)

Requirements

• Use xUnit testing framework
• Use seeded Random for deterministic tests
• All tests must pass in CI pipeline
• Good test naming conventions

Acceptance Criteria

• Test class for ICombatStrategy implementations
• MeleeStrategy damage calculation tested
• MagicStrategy damage calculation tested
• RangedStrategy damage calculation tested
• Test class for CombatEngine
• Player wins scenario tested
• Enemy wins scenario tested
• XP reward calculation tested
• Gold reward calculation tested
• Turn order verified
• Edge cases tested (zero health, max defense, zero attack)
• Uses seeded Random for deterministic behavior
• All tests pass in CI
• Tests follow naming conventions