Add Konami code invulnerability easter egg

[Copilot]

Implements Konami code (↑ ↑ ↓ ↓ ← → ← → B A) as an easter egg that grants invulnerability. When activated, enemies deal no damage.

Changes

• State tracking (game/state.go): Added KonamiSequence []string and Invulnerable bool to GameState. Tracks last 10 key presses and matches against Konami pattern.

• Damage prevention (game/state.go): Modified enemyAttacks() to return early when invulnerable.

• Input handling (game/game.go): Arrow keys and 'b'/'a' keys now feed into sequence detection via CheckKonamiCode().

• UI feedback (game/game.go): Status bar displays "INVULNERABLE" when active. Activation shows message: "KONAMI CODE ACTIVATED! You are now invulnerable!"

Example

// CheckKonamiCode tracks key sequence and activates invulnerability
func (gs *GameState) CheckKonamiCode(key string) {
    konamiCode := []string{"up", "up", "down", "down", "left", "right", "left", "right", "b", "a"}
    gs.KonamiSequence = append(gs.KonamiSequence, key)
    
    if len(gs.KonamiSequence) > 10 {
        gs.KonamiSequence = gs.KonamiSequence[len(gs.KonamiSequence)-10:]
    }
    
    if len(gs.KonamiSequence) == 10 && matches(gs.KonamiSequence, konamiCode) {
        gs.Invulnerable = true
    }
}

Tests cover correct/incorrect sequences and damage mechanics with/without invulnerability.

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• dl.google.com
  • Triggering command: /update-job-proxy /update-job-proxy (dns block)
  • Triggering command: /update-job-proxy /update-job-proxy DROP noffline test -e cation_Authority.pem noffline /opt/go/bin/test submodules | hea/usr/bin/git -trimpath git test -e CA_v1.pem /home/REDACTED/go/pkg/mod/golang.o/usr/share/ca-certificates/mozilla/Autoridad_de_Certificacion_Filist /bin/test -bool -buildtags mi-code-invulner-t test (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)

Original prompt

If the Konami code is entererd, the player becomes invulnerable. Monsters do no damage.

Created from Copilot CLI via the copilot delegate command.

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[leereilly]