Fix: Resolve vulnerability scanning issues

- Move utility scripts to cmd/tools/ to avoid main function conflicts
- Fix library_main.go imports and add build constraints
- Update go.mod to require go 1.24 (matching toolchain)
- Add proper build documentation for library vs standard builds
- Replace private imports with stub implementations

Resolves all vulnerability scanning errors:
✅ Multiple main function declarations
✅ Go version compatibility (go1.24 requirement)
✅ Missing private repository imports
✅ CGO compilation issues

Author: Mike Kuykendall

BUILD.md

@@ -0,0 +1,13 @@
+# ContextLite Build Instructions
+
+## Standard Build (Community Version)
+```bash
+go build -o contextlite ./cmd/contextlite
+```
+
+## Library Build (C Interface - requires private components)
+```bash
+go build -tags library -buildmode=c-shared -o libcontextlite.so library_main.go
+```
+
+Note: The library build requires access to private repository components and will produce stubs in the community version.