Add storage variables and contract inheritance to `entry-points` printer

[nisedo]

Summary

Enhances the entry-points printer to display state variables and contract inheritance alongside function entry points, providing a complete view of contract storage and entry points.

Changes

Added Features

• State variables table with types, storage slots, and inheritance info
• Full inheritance chain in contract headers (e.g., "Contract is Parent1 is Parent2")
• Constructor, receive, and fallback functions (previously excluded, now included in purple color)

Output Example

Before:

After:

Files Changed

• slither/printers/summary/entry_points.py - Enhanced implementation
• README.md - Updated description

Same usage: slither . --print entry-points

[nisedo]

Removed the Storage Slots column for a cleaner output (8c1009a):