fix(codex): make host-credential bottles actually authenticate

Debugging a live codex smolmachines bottle surfaced three independent
failures past the sign-in screen; fix each so forward_host_credentials
works end to end:

- codex_auth: dummy access/id tokens now inherit the *real* host token's
  exp instead of now+1h. Codex (0.135) refreshes when its local token's
  JWT exp lapses; with a placeholder refresh_token that refresh fails and
  drops to the sign-in screen. Aligning exp tracks the real token's life.

- prepare: set CODEX_CA_CERTIFICATE to the agent CA bundle for codex
  bottles. Codex is rustls and ignores the system store / NODE_EXTRA_CA_
  CERTS; it reads CODEX_CA_CERTIFICATE (fallback SSL_CERT_FILE) for custom
  roots across HTTPS + wss, so it must be pointed at the egress MITM CA or
  injection can't work without tls_passthrough.

- pipelock: auto tls_passthrough the Codex API hosts when
  forward_host_credentials is on. Egress injects the bearer before
  pipelock, whose header DLP then flags the JWT ("request header contains
  secret") and the retry storm trips its 429. passthrough host-gates the
  CONNECT but skips decrypt+rescan of egress-owned auth. The auto-added
  routes aren't in bottle.egress.routes, so the hosts are added explicitly.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

tests/unit/test_pipelock_allowlist.py

@@ -113,6 +113,25 @@ class TestTlsPassthrough(unittest.TestCase):
         ])))
         self.assertEqual(["api.openai.com"], passthrough)
 
+    def test_forward_host_credentials_passes_through_codex_hosts(self):
+        # Egress injects the host bearer on the Codex API hosts; pipelock
+        # must pass them through or its header DLP blocks the injected JWT
+        # ("request header contains secret"). These routes are auto-added
+        # (not in bottle.egress.routes), so passthrough is host-derived.
+        passthrough = pipelock_effective_tls_passthrough(_bottle({
+            "agent_provider": {
+                "template": "codex",
+                "forward_host_credentials": True,
+            },
+        }))
+        self.assertEqual(["api.openai.com", "chatgpt.com"], passthrough)
+
+    def test_no_codex_passthrough_without_forward_host_credentials(self):
+        passthrough = pipelock_effective_tls_passthrough(_bottle({
+            "agent_provider": {"template": "codex"},
+        }))
+        self.assertEqual([], passthrough)
+
 
 class TestSsrfIpAllowlist(unittest.TestCase):
     def test_default_empty(self):