chore: release v2.4.6 with improved npm compatibility and fixes

- fix color detection for cross-platform TTY compatibility
- enhance help command with npm-specific content and npx examples
- remove --install/--uninstall flags pending .claude/ integration testing
- update version across all files and documentation
- preserve implementation code for future release readiness

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@kaitranntt/ccs",
-  "version": "2.4.5",
+  "version": "2.4.6",
   "description": "Claude Code Switch - Instant profile switching between Claude Sonnet 4.5 and GLM 4.6",
   "keywords": [
     "cli",