tests: use pytest instead of unittest

pytest provides session scoped fixtures, making it much easier
to reuse resources across tests.

docs/nfc_auth.md

@@ -251,7 +251,7 @@ hard-coding the lab certificate.
 Run:
 
 ```bash
-.venv/bin/python -m unittest tests.integration.test_nfc_auth
+.venv/bin/pytest tests/integration/test_nfc_auth.py
 ```
 
 The test completes VIM login and the authd handshake (`200 Connect`)

docs/nfc_open.md

@@ -206,7 +206,7 @@ classic type 4 `NFC_SESSION_COMPLETE`.
 Run:
 
 ```bash
-.venv/bin/python -m unittest tests.integration.test_nfc_open
+.venv/bin/pytest tests/integration/test_nfc_open.py
 ```
 
 The test opens the temporary lab VMDK, asserts an opaque handle and

docs/nfc_read.md

@@ -105,7 +105,7 @@ Writes use the same 44-byte IO payload with opcode `2`; see
 `openvixdisklib/nfc_open.py`. Run:
 
 ```bash
-.venv/bin/python -m unittest tests.integration.test_nfc_read_write
+.venv/bin/pytest tests/integration/test_nfc_read_write.py
 ```
 
 The integration test writes and then reads the captured VDDK ranges

docs/reverse_engineering_procedure.md

@@ -9,9 +9,9 @@ NFC work can follow the same loop instead of rediscovering it.
 
 Scope so far: `VixDiskLib_ConnectEx` + `VixDiskLib_Open` +
 `VixDiskLib_Read` + `VixDiskLib_Write` against lab vCenter 8.0.1 /
-ESXi 8, transport `nbd`. Driver: `tests/integration/` (`TestBase`
-creates a temporary empty VM with a 10 GiB disk in `setUpClass` and
-destroys it in `tearDownClass`).
+ESXi 8, transport `nbd`. Driver: `tests/integration/` (the session-scoped
+`lab` fixture creates a temporary empty VM with a 10 GiB disk and
+destroys it when the pytest session ends).
 
 Rule from `AGENTS.md`: reuse pyVmomi for every public VIM operation.
 Only reimplement what pyVmomi does not expose.