feat: complete code cleanup and create feature parity plan

Major Architecture Improvements:
- Separate JavaScript library (lib/) with proper build system
- Go CLI with embedded library using go:embed
- Hot reload development with Air integration
- Library + CLI build pipeline with npm run build

Code Cleanup:
- Remove obsolete assets (insertr-cli/assets/editor/)
- Clean up package.json metadata and dependencies
- Update .gitignore for new architecture
- Remove unused 'marked' dependency

New Documentation:
- Add comprehensive TODO.md with feature gap analysis
- Document critical gaps between prototype and current library
- Create phased implementation plan for feature parity
- Update DEVELOPMENT.md with hot reload workflow
- Add LIBRARY.md documenting new architecture

Hot Reload System:
- Air watches both Go CLI and JavaScript library
- Library changes trigger: rebuild → copy → CLI rebuild → serve
- Seamless development experience across full stack

Next Steps:
- Current library is basic proof-of-concept (prompt() editing)
- Archived prototype has production-ready features
- Phase 1 focuses on professional forms and authentication
- Phase 2 adds validation and content persistence

insertr-cli/.air.toml

@@ -7,21 +7,21 @@ tmp_dir = "tmp"
   bin = "./tmp/insertr"
   cmd = "go build -o ./tmp/insertr ."
   delay = 1000
-  exclude_dir = ["assets", "tmp", "vendor", "testdata", "node_modules"]
+  exclude_dir = ["tmp", "vendor", "testdata", "node_modules", "dist"]
   exclude_file = []
   exclude_regex = ["_test.go"]
   exclude_unchanged = false
   follow_symlink = false
   full_bin = "./tmp/insertr servedev -i ../demo-site -p 3000"
-  include_dir = []
-  include_ext = ["go", "tpl", "tmpl", "html"]
+  include_dir = ["../lib/src"]
+  include_ext = ["go", "tpl", "tmpl", "html", "js"]
   include_file = []
   kill_delay = "0s"
   log = "build-errors.log"
   poll = false
   poll_interval = 0
   post_cmd = []
-  pre_cmd = []
+  pre_cmd = ["./scripts/rebuild-library.sh"]
   rerun = false
   rerun_delay = 500
   send_interrupt = false