docs(milestone): complete v1.15 — Nova Rebrand (tag v1.15.4)

P5 final-review-ship complete: dual-read fallback removed (REQ-164) —
core/env.py NOVA-only, .env.secrets load paths NOVA-only (G-106 retired),
nova_tagging.py hard-fails any acdl:* tag, legacy ACDL_* Gitea secrets
deleted, ACDL_LIFECYCLE_MODE/ACDL_LOCAL_TIER/ACDL_HITL_* exports removed
from scripts, SNS subject → Nova SoD halt (P1-2), bootstrap scripts
NOVA-only. Review: 2 P0 auto-fixed (duplicate delenv), P1-1/P1-2 resolved,
doc-drift fixed. Audit: tags v1.15.0-4 exist; traceability REQ-155..164
all complete; ARCHITECTURE naming table matches codebase. 615 pytest PASS;
run_ci.sh 3-stage PASS. NOVA_MIGRATION.md marked COMPLETE.

---ci---
project: acdl
phase: 5
milestone: v1.15
status: complete
phase_role: final
requirements:
  covered: [REQ-155, REQ-156, REQ-157, REQ-158, REQ-159, REQ-160, REQ-161, REQ-162, REQ-163, REQ-164]
  partial: []
---/ci---

core/env.py

@@ -1,19 +1,14 @@
-"""Dual-read environment helper (D-108, REQ-159, G-106).
+"""Environment helper (D-108, REQ-159, REQ-164).
 
-During the Nova rebrand transition window (P2–P4), every `NOVA_*`
-environment variable is the preferred source, with the legacy `ACDL_*`
-name as the fallback. This keeps deployments from breaking while the
-keys are rotated across `.env`, `.env.secrets`, Gitea repo secrets, and
-operator-managed process environments.
+During the Nova rebrand transition window (P2–P4), `get_env` read
+`NOVA_*` preferred with the legacy `ACDL_*` name as the fallback. **P5
+(REQ-164) removed the fallback** — `get_env` now reads `NOVA_*` only.
 
-`get_env(name, default=None)` resolves `NOVA_<name>` first, then falls
-back to `ACDL_<name>`, then returns `default` if neither is set.
-
-This helper is removed (NOVA-only) in P5 (REQ-164). Direct-read paths
-that bypass this helper (the `.env.secrets` shell export in
-`scripts/run_platform.sh` and the Python parser in
-`core/regression_verify.py`) mirror this contract inline per the G-106
-binding — see those sites for the dual-read shell/Python forms.
+`get_env(name, default=None)` resolves `NOVA_<name>`, then returns
+`default` if unset. Direct-read paths that bypass this helper (the
+`.env.secrets` shell export in `scripts/run_platform.sh` and the Python
+parser in `core/regression_verify.py`) were updated to NOVA-only in P5
+(the G-106 dual-read contract was retired with the fallback).
 """
 
 from __future__ import annotations
@@ -25,24 +20,12 @@ __all__ = ["get_env"]
 
 
 def get_env(name: str, default: Optional[str] = None) -> Optional[str]:
-    """Resolve a config value with a NOVA-preferred / ACDL-fallback read.
+    """Resolve a config value from the `NOVA_*` environment.
 
     `name` is the bare key WITHOUT the prefix (e.g. ``"AWS_ACCOUNT_ID"``).
-    The lookup order is:
-
-    1. ``NOVA_<name>`` (preferred)
-    2. ``ACDL_<name>`` (legacy fallback, removed in P5)
-    3. ``default``
-
-    Returns the first value that is present and non-empty, or ``default``
-    if neither env var is set. An explicitly-set empty string is treated
-    as "unset" so an operator cannot accidentally shadow the fallback
-    with a blank NOVA key.
+    Returns ``NOVA_<name>`` if set and non-empty, else ``default``.
     """
-    nova_val = os.environ.get(f"NOVA_{name}")
-    if nova_val:
-        return nova_val
-    acdl_val = os.environ.get(f"ACDL_{name}")
-    if acdl_val:
-        return acdl_val
+    val = os.environ.get(f"NOVA_{name}")
+    if val:
+        return val
     return default

core/local_emulators.py

@@ -502,6 +502,6 @@ if __name__ == "__main__":
     # Set both so the dual-read in is_local_tier() finds NOVA_* (preferred);
     # the ACDL_* alias stays for any unmigrated reader until P5.
     os.environ["NOVA_LOCAL_TIER"] = "1"
-    os.environ["ACDL_LOCAL_TIER"] = "1"  # legacy alias (dual-read fallback), removed in P5
+    # P5 (REQ-164): ACDL_LOCAL_TIER legacy alias removed (NOVA_* only)
     result = run_local_e2e(contract)
     print(json.dumps(result, indent=2))

core/regression_verify.py

@@ -315,13 +315,10 @@ def _load_aws_env() -> Dict[str, str]:
                     continue
                 if "=" in line:
                     k, v = line.split("=", 1)
-                    # G-106 binding: dual-read NOVA_* first, ACDL_* fallback.
-                    # The .env.secrets keys are renamed to NOVA_* in P2; the
-                    # ACDL_* fallback covers operators who haven't rotated
-                    # their local .env.secrets yet. Removed in P5.
-                    if k == "NOVA_AWS_ACCESS_KEY_ID" or k == "ACDL_AWS_ACCESS_KEY_ID":
+                    # P5 (REQ-164): dual-read fallback removed — NOVA_* only.
+                    if k == "NOVA_AWS_ACCESS_KEY_ID":
                         env["AWS_ACCESS_KEY_ID"] = v
-                    elif k == "NOVA_AWS_SECRET_ACCESS_KEY" or k == "ACDL_AWS_SECRET_ACCESS_KEY":
+                    elif k == "NOVA_AWS_SECRET_ACCESS_KEY":
                         env["AWS_SECRET_ACCESS_KEY"] = v
                     elif k == "AWS_DEFAULT_REGION":
                         env["AWS_DEFAULT_REGION"] = v

core/separation_of_duties.py

@@ -74,7 +74,7 @@ def route_halt_artifact(contract_id: str, violation_reason: str,
             sns.publish(
                 TopicArn=topic_arn,
                 Message=json.dumps(halt_payload),
-                Subject="ACDL SoD halt",
+                Subject="Nova SoD halt",
             )
             print(f"[halt-artifact] SNS published contract={contract_id} "
                   f"topic={topic_arn}", flush=True)