feat(mail): enhance mail configuration with getmail and dovecot settings

- Added getmail configuration generation using template files.
- Introduced postfix and dovecot configuration checksums for deployment.
- Created new dovecot configuration file and sieve script for email handling.
- Updated main.tf to utilize local variables for configuration management.
- Removed redundant external password hasher from main.tf.

feat(nginx): improve nginx configuration management

- Centralized nginx configuration into a local variable with checksum.
- Created separate config maps for default website configurations.
- Updated deployment to utilize new configuration structure.

feat(sftpgo): add SFTPGo application deployment

- Introduced SFTPGo with Kubernetes resources including namespace, config maps, and secrets.
- Configured SFTPGo with SMTP settings and AWS credentials.
- Implemented health checks and volume mounts for persistent storage.

refactor(seafile): remove Seafile module

- Deleted Seafile module and associated resources as part of cleanup.

terraform/modules/apps/sftpgo/provider.tf

@@ -0,0 +1,17 @@
+terraform {
+  required_version = "~>1.8"
+  required_providers {
+    kubernetes = {
+      source  = "hashicorp/kubernetes"
+      version = "~>2.18"
+    }
+    scaleway = {
+      source  = "scaleway/scaleway"
+      version = "~>2.13"
+    }
+    random = {
+      source  = "hashicorp/random"
+      version = "3.7.2"
+    }
+  }
+}