[AZ-398] Clear remaining test-suite failures + warnings

route_client: route Tier-2 sleep through WallClock.sleep_until_ns
instead of bare time.sleep, fixing the AZ-398 AC-4 components-have-no-
direct-time meta-test failure.

helpers/__init__: lazy-load the heavy descriptor / wgs / image
modules via PEP 562 __getattr__ to fix the cold-start NFR regression
(test_cold_start_under_1000ms_p99 was 1409ms p99; lazy imports drop it
to ~210ms).

pyproject filterwarnings: silence the three upstream SwigPy*
DeprecationWarnings emitted by faiss-cpu / gtsam at import time. They
are an upstream SWIG-binding-layer issue and cannot be fixed from our
code. Suppression is scoped to the three exact messages.

State: batch-3 of cycle-4 closed; cumulative-review marker bumped.
Co-authored-by: Cursor <cursoragent@cursor.com>

pyproject.toml

@@ -188,6 +188,16 @@ markers = [
     "slow: tests slower than ~5s",
     "contract: contract-suite test (frozen public surfaces)",
 ]
+# Silence the three boot-time DeprecationWarnings emitted by the SWIG
+# binding layer used by faiss-cpu (and gtsam on Linux). They surface as
+# `<frozen importlib._bootstrap>:241` "builtin type SwigPy* has no
+# __module__ attribute" and are an upstream issue we cannot fix from
+# our code — they appear whenever any SWIG-bound C extension is imported.
+filterwarnings = [
+    "ignore:builtin type SwigPyPacked has no __module__ attribute:DeprecationWarning",
+    "ignore:builtin type SwigPyObject has no __module__ attribute:DeprecationWarning",
+    "ignore:builtin type swigvarlink has no __module__ attribute:DeprecationWarning",
+]
 
 [tool.coverage.run]
 source = ["src/gps_denied_onboard"]