Refactor: replace hardcoded role strings with a typed Role constant

[ayush00git]

Role strings like \"faculty\", \"warden\", \"centrehead\", and \"admin\" are scattered as raw literals across multiple handler files. This makes them easy to mistype (already inconsistent — centrehead vs centre_head in different places) and impossible for the compiler to catch.

Affected locations

handlers/faculty_auth.go

• SendVerificationMail(..., "faculty") — lines 68, 86
• helpers.GenerateToken(..., "faculty") — line 129
• c.JSON(200, gin.H{..., "role": "faculty"}) — lines 145, 221
• services.SendPasswordResetMail(..., "faculty") — line 172

handlers/warden_auth.go

• SendVerificationMail(..., "warden") — lines 48, 65
• helpers.GenerateToken(..., "warden") — line 106
• c.JSON(200, gin.H{..., "role": "warden"}) — lines 122, 199
• services.SendPasswordResetMail(..., "warden") — line 150

handlers/centrehead_auth.go

• SendVerificationMail(..., "centrehead") — lines 48, 65
• helpers.GenerateToken(..., "centrehead") — line 106
• c.JSON(200, gin.H{..., "role": "centrehead"}) — lines 122, 198
• services.SendPasswordResetMail(..., "centrehead") — line 149

handlers/admin_auth.go

• helpers.GenerateToken(..., "admin") — line 69

handlers/auth.go (VerifyAccount / UserProfile switch-cases)

• case "faculty", case "warden", case "admin" — lines 39–43, 67–75

handlers/admin_post.go (AdminGetPost switch-cases)

• case "faculty", case "warden" — lines 269, 285

Fix

Add role constants to models/ (or a shared types package):

const (
    RoleFaculty    = "faculty"
    RoleWarden     = "warden"
    RoleCentreHead = "centrehead"
    RoleAdmin      = "admin"
)

Then replace every raw string literal above with the corresponding constant. The compiler will catch any future typo, and a rename only needs to happen in one place.

Note: centrehead_auth.go already uses "centrehead" while auth.go routes use "centre_head" in the URL path — consolidate on one canonical spelling when making this change.