Add Progressive Hint System for Better Learning Experience

[SyntaxSidekick]

Students need better guidance when stuck on questions.

Current State:

• Single hint per question (if any)
• No progressive disclosure

New Hint System:

• Multi-level hints (3 levels per question)
• Level 1: Conceptual hint
• Level 2: Technical direction
• Level 3: Near-solution guidance
• UI button to reveal next hint
• Track hint usage for analytics

UI Requirements:

• Expandable hint sections in About Question tab
• Visual progression indicator (1/3, 2/3, 3/3)
• Clear visual separation between hint levels

Database Changes:

• Update questionsDatabase.json structure
• Convert single "hint" to "hints" array

Priority: High - Significantly improves learning experience