fix(doctor): oMoMoMoMo branding, remove providers check, fix comment-checker detection

Rename header to oMoMoMoMo Doctor to match installation guide branding.
Remove providers check entirely — no longer meaningful for diagnostics.
Fix comment-checker detection by resolving @code-yeongyu/comment-checker package path
in addition to PATH lookup.

src/cli/doctor/format-shared.ts

@@ -27,7 +27,7 @@ export function stripAnsi(str: string): string {
 }
 
 export function formatHeader(): string {
-  return `\n${color.bgMagenta(color.white(" oMo Doctor "))}\n`
+  return `\n${color.bgMagenta(color.white(" oMoMoMoMo Doctor "))}\n`
 }
 
 export function formatIssue(issue: DoctorIssue, index: number): string {