feat(P3): Nova rebrand — SSM path + tag keys (REQ-161/162)

SSM path /acdl/{env}/{contractId}/{output} → /nova/... across
core/output_publisher + contract resolver + consumer docs. New
scripts/migrate_ssm_paths.py (copy/verify/delete, dry-run default).
AWS tag keys acdl:owner|environment|contract|cost-center|ref → nova:*
across terraform tagging + ABAC session policies (iam:ResourceTag/acdl:*
→ iam:ResourceTag/nova:*). nova_tagging.py hard mode (D-109 warn→hard).
tagging-standard.json tag-key values → nova:*. New
scripts/untag_acdl_keys.py (remove old acdl:* tags, dry-run default).
Test fixtures updated; pytest + run_ci.sh PASS.

---ci---
project: acdl
phase: 3
milestone: v1.15
status: execute
---/ci---

modules/l1/s3/terraform/locals.tf

@@ -6,8 +6,8 @@ locals {
   # Tags: merge caller-supplied tags with the module defaults.
   tags = merge(
     {
-      "acdl:owner"       = "acdl"
-      "acdl:environment" = "dev"
+      "nova:owner"       = "acdl"
+      "nova:environment" = "dev"
     },
     var.tags
   )