refactor(config): move Config struct from business layer to platform/config

Moved the Config struct (previously in internal/models/config.go) into internal/platform/config/types.go to align with clean architecture principles.

This change decouples runtime/infrastructure configuration from domain models:
- Configuration is an application/platform concern, not part of the business domain.
- Prevents potential circular imports between models and platform packages.
- Simplifies future integration with platform components (SCS sessions, CSRF, DB).

No functional changes to configuration loading structure and JSON schema remain the same; only the package location and imports were updated.

internal/models/config.go

@@ -1,40 +0,0 @@
-package models
-
-type Config struct {
-	CSRF struct {
-		CSRFKey string `json:"csrfKey"`
-	} `json:"csrf"`
-
-	Database struct {
-		Server                string `json:"server"`
-		Port                  int    `json:"port"`
-		DatabaseNamed         string `json:"databaseName"`
-		MaxOpenConnections    int    `json:"maxOpenConnections"`
-		MaxIdleConnections    int    `json:"maxIdleConnections"`
-		ConnectionMaxLifetime string `json:"connectionMaxLifetime"`
-		Username              string `json:"username"`
-		Password              string `json:"password"`
-	}
-
-	HttpServer struct {
-		Port           int    `json:"port"`
-		Address        string `json:"address"`
-		ProductionMode bool   `json:"productionMode"`
-	} `json:"httpServer"`
-
-	License struct {
-		APIURL string `json:"apiUrl"`
-		APIKey string `json:"apiKey"`
-	} `json:"license"`
-
-	Session struct {
-		AuthKeyPath       string `json:"authKeyPath"`
-		EncryptionKeyPath string `json:"encryptionKeyPath"`
-		Name              string `json:"name"`
-	} `json:"session"`
-
-	Site struct {
-		SiteName           string `json:"siteName"`
-		CopyrightYearStart int    `json:"copyrightYearStart"`
-	} `json:"site"`
-}