Add channel test providers for Email, Slack, Teams, and Webhook

- Implemented EmailChannelTestProvider to generate email preview payloads.
- Implemented SlackChannelTestProvider to create Slack message previews.
- Implemented TeamsChannelTestProvider for generating Teams Adaptive Card previews.
- Implemented WebhookChannelTestProvider to create webhook payloads.
- Added INotifyChannelTestProvider interface for channel-specific preview generation.
- Created ChannelTestPreviewContracts for request and response models.
- Developed NotifyChannelTestService to handle test send requests and generate previews.
- Added rate limit policies for test sends and delivery history.
- Implemented unit tests for service registration and binding.
- Updated project files to include necessary dependencies and configurations.

deploy/tools/validate-profiles.sh

@@ -9,6 +9,7 @@ compose_profiles=(
   "docker-compose.dev.yaml:env/dev.env.example"
   "docker-compose.stage.yaml:env/stage.env.example"
   "docker-compose.airgap.yaml:env/airgap.env.example"
+  "docker-compose.mirror.yaml:env/mirror.env.example"
 )
 
 docker_ready=false
@@ -36,6 +37,7 @@ helm_values=(
   "$HELM_DIR/values-dev.yaml"
   "$HELM_DIR/values-stage.yaml"
   "$HELM_DIR/values-airgap.yaml"
+  "$HELM_DIR/values-mirror.yaml"
 )
 
 if command -v helm >/dev/null 2>&1; then