feat(bitdefender): doc-verify assignPolicy/push + add full-API build-out tracker

- assign_policy: add inheritFromAbove option; mark VERIFIED via official docs
  (policyId/targetIds/forcePolicyInheritance/inheritFromAbove; not applied to
  ENFORCED-policy targets).
- setPushEventSettings: documented serviceType (splunk/cef/jsonRPC), TLS 1.2+
  receiver requirement, subscribeToEventTypes event-flag map; webhook receiver
  pattern noted.
- api-reference.md: cite GravityZone Support Center as authoritative source.
- add references/BUILDOUT.md — master checklist to implement every API method
  module-by-module; seeded with current done/todo/dead state.
- memory: reference_gravityzone_support (+ index).

selftest 42/42.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

.claude/skills/bitdefender/scripts/gz_client.py

@@ -633,17 +633,22 @@ class GravityZoneClient:
         policy_id: str,
         target_ids: list[str],
         force_inheritance: bool = False,
+        inherit_from_above: bool = False,
     ) -> Any:
         """Assign an existing policy to endpoints/groups (network.assignPolicy).
 
-        Param shape VERIFIED LIVE via validation probe (2026-06-21): requires
-        `policyId` and `targetIds` (a list of endpoint/group ids).
-        `forcePolicyInheritance` is optional. STATE-CHANGING — gate at the call
-        site behind --confirm.
+        Param shape VERIFIED against the official docs + live validation probe
+        (2026-06-21): `policyId` and `targetIds` (endpoint/container ids) are
+        required; `forcePolicyInheritance` and `inheritFromAbove` are optional
+        bools. NOTE: the policy is NOT applied to targets that already carry an
+        ENFORCED policy. STATE-CHANGING — gate at the call site behind --confirm.
+        Docs: bitdefender.com/business/support/en/77212-924802-assignpolicy.html
         """
         params: dict = {"policyId": policy_id, "targetIds": target_ids}
         if force_inheritance:
             params["forcePolicyInheritance"] = True
+        if inherit_from_above:
+            params["inheritFromAbove"] = True
         return self._jsonrpc_request("network", "assignPolicy", params)
 
     def list_scan_tasks(