Add config loading and dry-run validation

examples/fan-out.yml

@@ -0,0 +1,32 @@
+pipelines:
+  - id: reports
+    source:
+      backend: local
+      path: /var/spool/distributor/reports
+    validation:
+      on_digest_mismatch: fail
+    destinations:
+      - id: markdown-archive
+        backend: s3
+        endpoint: https://s3.example.com
+        bucket: reports
+        prefix: archive
+        region: us-east-1
+        force_path_style: true
+        credentials:
+          access_key_id_env: DISTRIBUTOR_S3_ACCESS_KEY_ID
+          secret_access_key_env: DISTRIBUTOR_S3_SECRET_ACCESS_KEY
+        publish:
+          source: true
+          html: false
+      - id: static-site
+        backend: ssh
+        uri: ssh://deploy@example.com:22
+        path: /srv/www/reports
+        publish:
+          source: false
+          html: true
+        transform:
+          markdown_to_html:
+            enabled: true
+            mode: sidecar