Cover the deterministic parser with golden-file tests over 55 real
scrubbed .eml fixtures (both comment sub-shapes, username Submitted-By,
address present/absent, br+CRLF assign addresses), fail-closed
validation-gate rules, adversarial and prompt-injection cases that must
route to ai_fallback or parse without corrupting other fields, the issue
#23 comment_id idempotency invariants, and the Bedrock-fallback dispatch
plus EMF-metric emission with a mocked invoke_model.
Extend pytest.ini testpaths to discover the co-located suite, and update
tests/conftest.load_handler to put a handler's own directory on sys.path
so the WO handler's new `from template_parser import ...` resolves under
the existing shared handler tests. Point test_local.py at the new
template-first + Bedrock flow.
Refs: #23
The repo had no automated tests, so regressions in the email
parsing pipeline could only be caught manually. The reusable
ci-python-sam workflow already supports a run-tests input at the
pinned SHA; enable it and add a first suite covering the pure
functions pad_zip and parse_raw_email.
tests/conftest.py sets AWS_DEFAULT_REGION and dummy credentials
before any handler import because the handlers create boto3
clients at module import time, and loads each handler.py via
importlib under a unique module name since the files share a
basename. pytest.ini scopes discovery to tests/ so the manual
test_local.py script at the repo root is not collected.
