fix(hanzoai): 3.1.1 — guard optional ZAP import so import hanzoai works without the [zap] extra

zap.py is an httpx.BaseTransport; httpx is not a base dep (client core is urllib3).
3.1.0 imported zap.py eagerly in __init__, so `import hanzoai` crashed on missing
httpx in any clean install. Guard the import (try/except ImportError) and declare
httpx under the [zap] extra. import hanzoai now works with or without extras.

pkg/hanzoai/__init__.py

@@ -18,16 +18,21 @@
 __version__ = "1.0.0"
 
 
-# Optional ZAP-native transport (opt-in). Imported lazily inside `zap` so that
-# `import hanzoai` still works when the optional `hanzo-zap` extra is not installed.
-# These names are additive and intentionally NOT part of the locked `__all__`.
-from . import zap as zap
-from .zap import (
-    ZapTransport as ZapTransport,
-    AsyncZapTransport as AsyncZapTransport,
-    zap_http_client as zap_http_client,
-    async_zap_http_client as async_zap_http_client,
-)
+# Optional ZAP-native transport (opt-in via the `zap` extra). The transport is an
+# httpx.BaseTransport, so `zap` requires httpx + hanzo-zap (neither is a base dep —
+# the client core is urllib3). Guard the import so `import hanzoai` still works when
+# the extra is absent; the names appear only when `pip install hanzoai[zap]` is used.
+# Additive and intentionally NOT part of the locked `__all__`.
+try:
+    from . import zap as zap
+    from .zap import (
+        ZapTransport as ZapTransport,
+        AsyncZapTransport as AsyncZapTransport,
+        zap_http_client as zap_http_client,
+        async_zap_http_client as async_zap_http_client,
+    )
+except ImportError:  # pragma: no cover - hanzoai[zap] not installed
+    pass
 
 # Define package exports
 __all__ = [

pyproject.toml

@@ -1,6 +1,6 @@
 [project]
 name = "hanzoai"
-version = "3.1.0"
+version = "3.1.1"
 description = "The official Python library for the Hanzo API"
 dynamic = ["readme"]
 license = "BSD-3-Clause"
@@ -34,7 +34,7 @@ classifiers = [
 llm = ["hanzo-llm>=1.0.0"]
 # Optional ZAP-native binary transport (hanzoai.zap). Off by default; opt in via
 # `hanzoai.zap_http_client(...)`. hanzo-zap pulls in zap-proto for the wire codec.
-zap = ["hanzo-zap>=0.7.0"]
+zap = ["hanzo-zap>=0.7.0", "httpx>=0.27.0"]
 
 [project.urls]
 Homepage = "https://github.com/hanzoai/python-sdk"