test: respx suite at the HTTP boundary; type-check tests (ratchet resolved)

[Datata1]

Implements plans/refactor/06-test-suite-http-boundary.md:

• Add respx (dev). New shared fixtures: mock_api (respx router on the test base URL) and sdk (opened CodesphereSDK against it)
• tests/test_exceptions.py: full raise_for_status matrix over real httpx.Response objects (status->class for every exported exception, message-key extraction incl. joined error lists, non-JSON bodies, Retry-After parsing incl. non-numeric, APIError request context and str), default constructors for all 10 exception classes, plus end-to-end error surfacing through the real transport (404/429/ timeout/connect)
• tests/core/test_execute_operation.py: executor behavior on the real wire — URL building from path params, auth header, input_model validation stopping bad payloads before any request, empty-dict body regression, NoneType responses, response validation, and bound ResourceList items making follow-up calls
• tests/test_http_client.py: transport lifecycle (idempotent open, close-without-open), the full httpx->SDK error mapping matrix, timeout/stream_timeout properties, stream() passthrough
• Coverage: exceptions/config/http_client at 100%, core/handler at 96%
• ty ratchet fully resolved: tests/ removed from [tool.ty.src] exclude; the whole repo (src + tests) now type-checks. Fallout fixed properly where real (env_vars set/delete annotations didn't admit list[EnvVar]; isinstance narrowing in delete; typed workspace configs in the integration conftest) and suppressed surgically where ty is wrong (pytest.skip/fail signature resolution, funneled through skip_test/ fail_test helpers)
• CONTRIBUTING.md documents the mocking policy: new tests mock the transport (respx), never SDK internals

[github-actions]

🛡️ Bandit Security Scan Results

✅ No security issues found by Bandit.

[github-actions]

Pytest Coverage Report

File	Stmts	Miss	Branch	BrPart	Cover	Missing
__init__.py	9	0	0	0	100%
client.py	40	0	6	0	100%
config.py	9	0	0	0	100%
exceptions.py	94	0	38	0	100%
http_client.py	59	0	6	0	100%
utils.py	10	2	4	1	79%	9->10, 10–11
core
__init__.py	4	0	0	0	100%
base.py	55	0	2	0	100%
handler.py	59	3	18	0	96%	80–82
operations.py	15	0	0	0	100%
resources
__init__.py	0	0	0	0	100%
resources/metadata
__init__.py	3	0	0	0	100%
operations.py	6	0	0	0	100%
resources.py	13	0	0	0	100%
schemas.py	28	0	0	0	100%
resources/team
__init__.py	5	0	0	0	100%
operations.py	8	0	0	0	100%
resources.py	11	0	0	0	100%
schemas.py	27	0	0	0	100%
resources/team/domain
__init__.py	3	0	0	0	100%
operations.py	11	0	0	0	100%
resources.py	16	0	0	0	100%
schemas.py	55	5	0	0	91%	67, 69, 72, 75–76
resources/team/usage
__init__.py	3	0	0	0	100%
operations.py	4	0	0	0	100%
resources.py	43	2	8	2	92%	99->102, 102, 162->165, 165
schemas.py	70	7	6	5	84%	66->67, 67, 72–73, 76, 84–86
resources/workspace
__init__.py	5	0	0	0	100%
envVars.py	4	0	0	0	100%
operations.py	12	0	0	0	100%
resources.py	16	2	4	2	80%	13->14, 14, 19->20, 20
schemas.py	99	14	6	6	81%	100–101, 103–109, 115–116, 118, 142, 161
resources/workspace/env_vars
__init__.py	3	0	0	0	100%
operations.py	7	0	0	0	100%
resources.py	26	2	12	4	84%	33->35, 35–36, 38->exit
schemas.py	4	0	0	0	100%
resources/workspace/git
__init__.py	3	0	0	0	100%
operations.py	8	0	0	0	100%
resources.py	15	0	4	0	100%
schemas.py	4	0	0	0	100%
resources/workspace/landscape
__init__.py	3	0	0	0	100%
operations.py	12	0	0	0	100%
resources.py	96	7	36	8	89%	28->29, 29, 129->132, 135->138, 161->162, 162–163, 165->160, 168->169, 169, 173–175
schemas.py	290	29	10	4	89%	113–114, 117, 122–123, 126–127, 130, 135–137, 140–141, 144, 251, 258–259, 334–336, 338–340, 342–343, 458–459, 466–467
resources/workspace/logs
__init__.py	3	0	0	0	100%
operations.py	5	0	0	0	100%
resources.py	175	50	60	37	63%	66->68, 68, 97–98, 104, 106–108, 110, 113–114, 117, 120–121, 123–126, 128–129, 132–133, 135–136, 138–139, 141–143, 145–146, 148–152, 154–155, 157–159, 161–166, 179–180, 252–253
schemas.py	22	0	0	0	100%
TOTAL	1472	123	220	69	89%

Test Execution Summary

Tests	Skipped	Failures	Errors	Time
366	0 💤	0 ❌	0 🔥	4.127s ⏱️