fix: resolve missing ~/.ccs/.claude/ directory during npm install (v4.3.7) (#16)

* fix(postinstall): make ora dependency optional to fix missing ~/.ccs/.claude/ directory

The root cause was that `ora` module was not available during `npm install`
when the postinstall script runs, causing both:
- .claude/ directory copy to fail (ClaudeDirInstaller)
- Symlink creation to fail (ClaudeSymlinkManager)

This resulted in the ~/.ccs/.claude/ directory not being created.

Changes:
- Made ora import optional in ClaudeDirInstaller
- Made ora import optional in ClaudeSymlinkManager
- Both classes now gracefully fallback to console.log when ora is unavailable
- Postinstall now successfully creates ~/.ccs/.claude/ and symlinks

Tested: Clean install now properly creates all directories and symlinks

* chore: bump version to 4.3.7

Version 4.3.7 - Postinstall Fix Release

Changes:
- Fixed missing ~/.ccs/.claude/ directory during npm install
- Made ora dependency optional in installer utilities
- Added CHANGELOG entry documenting the fix

Files updated:
- VERSION: 4.3.6 -> 4.3.7
- package.json: version updated
- lib/ccs: version string updated
- lib/ccs.ps1: version string updated
- installers/install.sh: version string updated
- installers/install.ps1: version string updated
- CHANGELOG.md: added 4.3.7 release notes

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@kaitranntt/ccs",
-  "version": "4.3.6",
+  "version": "4.3.7",
   "description": "Claude Code Switch - Instant profile switching between Claude Sonnet 4.5 and GLM 4.6",
   "keywords": [
     "cli",