SK-2954: Confirm all four v3 EnvUrls (DEV/SANDBOX/STAGE/PROD)

All four were already pattern-derived correctly; now confirmed against
the authoritative values and no longer flagged unconfirmed. Added
PROD/SANDBOX/STAGE resolve_vault_url test coverage alongside the
existing DEV test.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

Author: saileshwar-skyflow

v3/skyflow/utils/enums/_env_urls.py

@@ -2,9 +2,8 @@
 
 
 class EnvUrls(Enum):
-    """v3 vault hosts -- a different subdomain than v2 (skyvault vs. vault). Only DEV is
-    confirmed against a live vault; the rest are pattern-derived and unconfirmed."""
-    DEV = "skyvault.skyflowapis.dev"                    # confirmed against a live vault
-    PROD = "skyvault.skyflowapis.com"                   # UNCONFIRMED -- pattern-derived
-    SANDBOX = "skyvault.skyflowapis-preview.com"        # UNCONFIRMED -- pattern-derived
-    STAGE = "skyvault.skyflowapis.tech"                 # UNCONFIRMED -- pattern-derived
+    """v3 vault hosts -- a different subdomain than v2 (skyvault vs. vault). All four confirmed."""
+    DEV = "skyvault.skyflowapis.dev"
+    PROD = "skyvault.skyflowapis.com"
+    SANDBOX = "skyvault.skyflowapis-preview.com"
+    STAGE = "skyvault.skyflowapis.tech"

v3/tests/vault/client/test__client.py

@@ -15,14 +15,26 @@ def test_is_a_base_vault_client(self):
 
     # ------------------------------------------------------------------ #
     # resolve_vault_url — v3's own domain (skyvault.skyflowapis.*), confirmed
-    # against a real vault to differ from v2's (vault.skyflowapis.*) for the
-    # same cluster_id/env -- reusing v2's derivation here 404'd.
+    # to differ from v2's (vault.skyflowapis.*) for the same cluster_id/env
+    # -- reusing v2's derivation here 404'd. All four envs confirmed.
     # ------------------------------------------------------------------ #
 
-    def test_resolve_vault_url_uses_v3_skyvault_domain(self):
+    def test_resolve_vault_url_uses_v3_skyvault_domain_dev(self):
         url = self.vault_client.resolve_vault_url("qhdmceurtnlz", Env.DEV, "myvault")
         self.assertEqual(url, "https://qhdmceurtnlz.skyvault.skyflowapis.dev")
 
+    def test_resolve_vault_url_uses_v3_skyvault_domain_prod(self):
+        url = self.vault_client.resolve_vault_url("qhdmceurtnlz", Env.PROD, "myvault")
+        self.assertEqual(url, "https://qhdmceurtnlz.skyvault.skyflowapis.com")
+
+    def test_resolve_vault_url_uses_v3_skyvault_domain_sandbox(self):
+        url = self.vault_client.resolve_vault_url("qhdmceurtnlz", Env.SANDBOX, "myvault")
+        self.assertEqual(url, "https://qhdmceurtnlz.skyvault.skyflowapis-preview.com")
+
+    def test_resolve_vault_url_uses_v3_skyvault_domain_stage(self):
+        url = self.vault_client.resolve_vault_url("qhdmceurtnlz", Env.STAGE, "myvault")
+        self.assertEqual(url, "https://qhdmceurtnlz.skyvault.skyflowapis.tech")
+
     @patch("skyflow.vault.client.client.SkyflowAuth")
     def test_initialize_api_client_does_not_pass_token(self, mock_skyflow_auth):
         """v3's generated client has no `token` param at all -- unlike v2, nothing should be