v1.0.6: Typing Statistics and Performance Tracking

[Kiolk]

Description

This PR introduces comprehensive typing statistics and performance tracking to the Typing Training plugin.

Changes in v1.0.6

• Performance Chart: Added a visual XY chart using JFreeChart at the end of each session showing progress over time (Words Per Minute, Errors Per Minute, and Accuracy).
• Unified Statistics View: Merged the final session summary and the performance chart into a single, comprehensive dialog for a better user experience.
• Persistent Statistics: Implemented project-level persistence using PersistentStateComponent. Typing performance is now saved in typingStatistics.xml and available across IDE sessions.
• Detailed Logging: Added internal logging for typing events. Every key typed, error made, and final session result is recorded in the IDE log (idea.log).
• X-Axis Formatting: Improved chart visualization by ensuring the "Attempt" axis shows whole numbers only.
• Build Optimization: Disabled buildSearchableOptions task to improve build performance.

Technical Details

• Added org.jfree:jfreechart:1.5.6 dependency.
• Created TypingResult model and TypingService for state management.
• Replaced multiple pop-up messages with a single StatisticsDialog.