Remove password reset functionality

Backend:
- Remove ForgotPassword API handler
- Remove password reset token model and database table
- Remove email service for sending reset emails
- Remove SMTP configuration

Frontend:
- Remove /auth/forgot page
- Remove forgot password link from login page
- Remove forgot route from auth-only routes check

backend/internal/db/imc_users.go

@@ -1,7 +1,5 @@
 package db
 
-import "time"
-
 // =============================================================================
 // Admin User (ImcUser) Operations
 // These functions manage admin users who can log into the web interface.
@@ -189,40 +187,3 @@ func (d *DB) IsUserInDomain(userID, domainID uint) (bool, error) {
 	err := d.Model(&ImcUserDomain{}).Where("user_id = ? AND domain_id = ?", userID, domainID).Count(&count).Error
 	return count > 0, err
 }
-
-// =============================================================================
-// Password Reset Tokens
-// These functions manage one-time tokens for password reset.
-// =============================================================================
-
-// CreatePasswordResetToken creates a new password reset token.
-// userID: the ID of the user requesting password reset.
-// token: the random token string.
-// expiresAt: when this token becomes invalid.
-func (d *DB) CreatePasswordResetToken(userID uint, token string, expiresAt time.Time) error {
-	resetToken := PasswordResetToken{
-		UserID:    userID,
-		Token:     token,
-		ExpiresAt: expiresAt,
-	}
-	return d.Create(&resetToken).Error
-}
-
-// GetValidPasswordResetToken looks up a valid (unused, not expired) reset token.
-// token: the token string to look up.
-// Returns: the token if valid, or an error if not found/expired/used.
-func (d *DB) GetValidPasswordResetToken(token string) (*PasswordResetToken, error) {
-	var resetToken PasswordResetToken
-	// Check token exists, hasn't been used, and hasn't expired.
-	err := d.Where("token = ? AND used = false AND expires_at > ?", token, time.Now()).First(&resetToken).Error
-	if err != nil {
-		return nil, err
-	}
-	return &resetToken, nil
-}
-
-// MarkResetTokenUsed marks a token as used (prevents reuse).
-// token: the token string to mark as used.
-func (d *DB) MarkResetTokenUsed(token string) error {
-	return d.Model(&PasswordResetToken{}).Where("token = ?", token).Update("used", true).Error
-}