feat(py): step 3 — full latprobe package with --verbose flag

Adds the complete Python port of the Go latprobe tool plus diagnostic
verbose output that the Go version does not yet have.

Package (python/latprobe/):
- probe.py: raw-socket HTTP timing with CertInfo/VerboseDetail dataclasses;
  TTFB loop accumulates to \r\n\r\n so headers are parseable without changing
  t_first_byte semantics; captures resolved IP, TLS version/cipher/bits,
  verified cert (via getpeercert()), and all response headers when verbose=True
- aggregate.py: summarize() → per-phase min/avg/max PhaseStats
- cli.py: injectable run(args,stdout,stderr)->int; argparse with injected
  streams; ThreadPoolExecutor concurrency across URLs; four text-rendering
  branches; JSON output; worst-exit-code accumulation; -v/--verbose flag
  appends IP/TLS/cert/header block after every timing table; JSON extended
  with "verbose" object (omitted when flag absent)
- duration.py: parse Go-style duration strings (10s, 500ms, 2m, bare seconds)
- Exit codes: 0 ok, 1 usage, 2 dns, 3 connect, 4 timeout, 5 tls, 6 http≥400

Tests:
- test_probe.py: 18 hermetic tests (success, 404, DNS/connect/timeout/scheme
  failures, partial-phase invariants, verbose detail fields)
- test_cli.py: 38 hermetic tests (usage errors, single/aggregate/failure text,
  worst-code, --fail, JSON schema/ordering/grouping, verbose text and JSON)
- test_integration.py: 45 tests against live internet services (badssl.com for
  TLS errors, real cert/IP/header validation in verbose mode)

Makefile: PYTHONPATH fix, fnmatch pattern test_[!i]*.py to exclude
integration tests from py-test, new py-test-integration target

Docs: docs/usage/py-latprobe.md, python/configs/usage-latprobe.md (runnable
reference with captured output), plans for both the package and verbose feature

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Makefile

@@ -112,11 +112,15 @@ py-run: ## py: run the full latprobe package (pass flags via ARGS="…")
 	cd $(PY_DIR) && $(PYTHON) -m latprobe $(ARGS)
 
 .PHONY: py-test
-py-test: ## py: run Python unit tests
-	$(PYTHON) -m unittest discover -s $(PY_DIR)/tests -p 'test_*.py' -v 2>&1 || true
+py-test: ## py: run Python unit tests (local, hermetic)
+	PYTHONPATH=$(PY_DIR) $(PYTHON) -m unittest discover -s $(PY_DIR)/tests -p 'test_[!i]*.py' -v $(ARGS)
+
+.PHONY: py-test-integration
+py-test-integration: ## py: run integration tests against live internet services (~30 s)
+	PYTHONPATH=$(PY_DIR) $(PYTHON) -m unittest discover -s $(PY_DIR)/tests -p 'test_integration.py' -v $(ARGS)
 
 .PHONY: py-check
-py-check: py-test ## py: run Python test gate
+py-check: py-test ## py: run Python test gate (hermetic only)
 
 .PHONY: py-clean
 py-clean: ## py: remove Python bytecode and __pycache__ dirs