Add Level Selection Menu for Better Navigation

[Itx-Psycho0]

Problem

Players must complete levels sequentially. Cannot jump to specific patterns they want to learn or replay completed levels.

Proposed Solution

Create a main menu screen showing all 4 levels:

• Visual cards for each level
• Lock/unlock status based on completion
• Brief description of what pattern each teaches
• "Play" button to launch level
• Progress indicators

Benefits

• Improved user experience and navigation
• Allows targeted learning (jump to specific pattern)
• Shows player progress visually
• Professional game standard feature

Implementation Approach

• New scene: main_menu.tscn
• Save/load completion status with ConfigFile
• Level cards with thumbnails and descriptions
• Unlock levels based on previous completion

I'm willing to implement this!

[Itx-Psycho0]

/assign

[Itx-Psycho0]

It will take after solving issue no. #10