feat: Gotify CRUD + internal handler dispatch for notification service

- Add internal handler support to ServiceAdapter (Handler field)
- Dispatcher routes to internal handler when set (no reverse proxy)
- GotifyClient: full CRUD (send/list/delete messages, CRUD applications)
- Refactor notification handler: route by X-Resource header, not body format
- Register notification as ServiceAdapter with auth required
- Resources: send-email, send-message, list-messages, delete-message,
  delete-all-messages, list-applications, create-application, delete-application
- Update examples: sendmsg-email.sh, gotify-crud.sh
- Env vars: GOTIFY_URL, GOTIFY_APP_TOKEN, GOTIFY_CLIENT_TOKEN

examples/gotify-crud.sh

@@ -0,0 +1,62 @@
+#!/bin/bash
+# Example: Gotify CRUD operations via notification service (X-Service routing)
+
+BASE_URL="${1:-https://api.riotpiao.com}"
+AUTH_TOKEN="${2:-}"
+AUTH="-H \"Authorization: Bearer $AUTH_TOKEN\""
+
+echo "=== Send Gotify Message ==="
+curl -s -X POST "$BASE_URL" \
+  -H "X-Service: notification" \
+  -H "X-Resource: send-message" \
+  -H "Content-Type: application/json" \
+  -H "Authorization: Bearer $AUTH_TOKEN" \
+  -d '{
+    "title": "Deployment Complete",
+    "message": "homelab-frontend v1.2.0 deployed to production",
+    "priority": 5
+  }' | jq .
+
+echo ""
+echo "=== List Messages ==="
+curl -s -X GET "$BASE_URL?limit=10" \
+  -H "X-Service: notification" \
+  -H "X-Resource: list-messages" \
+  -H "Authorization: Bearer $AUTH_TOKEN" | jq .
+
+echo ""
+echo "=== List Applications ==="
+curl -s -X GET "$BASE_URL" \
+  -H "X-Service: notification" \
+  -H "X-Resource: list-applications" \
+  -H "Authorization: Bearer $AUTH_TOKEN" | jq .
+
+echo ""
+echo "=== Create Application ==="
+curl -s -X POST "$BASE_URL" \
+  -H "X-Service: notification" \
+  -H "X-Resource: create-application" \
+  -H "Content-Type: application/json" \
+  -H "Authorization: Bearer $AUTH_TOKEN" \
+  -d '{
+    "name": "my-monitor",
+    "description": "Monitoring alerts"
+  }' | jq .
+
+echo ""
+echo "=== Delete Message (by ID) ==="
+curl -s -X DELETE "$BASE_URL" \
+  -H "X-Service: notification" \
+  -H "X-Resource: delete-message" \
+  -H "Content-Type: application/json" \
+  -H "Authorization: Bearer $AUTH_TOKEN" \
+  -d '{"id": 1}' | jq .
+
+echo ""
+echo "=== Delete Application (by ID) ==="
+curl -s -X DELETE "$BASE_URL" \
+  -H "X-Service: notification" \
+  -H "X-Resource: delete-application" \
+  -H "Content-Type: application/json" \
+  -H "Authorization: Bearer $AUTH_TOKEN" \
+  -d '{"id": 1}' | jq .