feat(doctor): add --help flag with comprehensive command documentation

- Add showHelp() with usage, options, checks, examples, exit codes
- Update handleDoctorCommand to accept args array instead of boolean
- Update ccs.ts to pass restArgs to doctor command
- Add doctor to CLAUDE.md Help Location Reference table

src/ccs.ts

@@ -340,8 +340,8 @@ async function main(): Promise<void> {
 
   // Special case: doctor command
   if (firstArg === 'doctor' || firstArg === '--doctor') {
-    const shouldFix = args.includes('--fix') || args.includes('-f');
-    await handleDoctorCommand(shouldFix);
+    const restArgs = args.slice(args.indexOf(firstArg) + 1);
+    await handleDoctorCommand(restArgs);
     return;
   }