[Matteeh]

Replace the robot arm visualization in the "How it Works" factory animation with a lamp that rains code, better representing how osq uses AI to build tasks. Update documentation and navigation to reflect the new visual metaphor.

Changes

Factory animation (HowItWorks.astro):

• Removed two robot arm objects (armBack and armFront) with their joint animations
• Added a lamp structure with base, post, head, and shade that illuminates during the build phase
• Implemented a "raining code" effect: five columns of binary digits falling from the lamp's shade into the task box, each with independent timing and animation
• Updated the factory title description to reference the lamp instead of robot arms
• Adjusted retry path coordinates to account for the new lamp height
• Updated badge position for the build phase (from z:24 to z:28)
• Replaced work/work2 keyframe animations with shade, beam, rain, and fall animations that sync with the 16-second factory loop

Documentation:

• Moved feature cards from a separate Features component into the main docs index as inline lists under "What you get" and "Coming in the rebuild" sections
• Removed Features.astro and FeatureGrid.astro components
• Removed docs/src/data/features.ts data file
• Updated navigation to remove Features and Roadmap links, replacing them with Get Started link
• Updated GetStarted component to show supported agents inline

Ledger animation timing:

• Synchronized pulse animation delays with actual factory step timings (0.02s, 0.2s, 0.44s, 0.58s, 0.88s) instead of fixed 0.6s intervals
• Changed pulse animation from 3s to 16s to match the factory loop duration

Documentation structure:

• Updated README.md to reflect removal of features data file