Consolidate documentation, bump to v1.2.1

Condense CLAUDE.md from ~1960 to ~160 lines keeping only essential
architecture and lessons learned. Merge INSTALL.md into README.md
and IMPLEMENTATION.md into CLAUDE.md, then delete the source files.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

CHANGELOG.md

@@ -5,6 +5,20 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [1.2.1] - 2026-03-01
+
+### Changed
+
+- Consolidated documentation: merged INSTALL.md into README.md, merged IMPLEMENTATION.md into CLAUDE.md
+- Condensed CLAUDE.md from ~1960 lines to ~160 lines, keeping only essential architecture and lessons learned
+- README.md now includes full installation guide, usage tutorial, and troubleshooting section
+- Cleaned up .gitignore
+
+### Removed
+
+- INSTALL.md (content merged into README.md)
+- IMPLEMENTATION.md (content merged into CLAUDE.md)
+
 ## [1.2.0] - 2026-03-01
 
 ### Fixed