v0.2.1

fix(detector): stop leaking memory when a lib init keeps failing (#14)

The detector wrappers cache the library init failure and re-raise the same
exception object on every subsequent init() call to fail fast. Re-raising one
object is a leak: CPython appends a frame to its __traceback__ on each raise,
and those frames retain the caller's (detect()) locals indefinitely.

On a hybrid NVIDIA+AMD host where ROCm SMI init fails permanently, detect()
calls rsmi_init() every heartbeat/metrics tick, so anonymous RSS grows without
bound (gpustack/gpustack#5342).

Raise a fresh clone of the cached exception instead, via a new
clone_exception() helper. It clones with BaseException.__new__ + a copy of
args/__dict__ rather than type(exc)(*exc.args), because some binding error
types (e.g. amdsmi's AmdSmiLibraryException) take an error code and leave args
empty, so they can't be reconstructed from args.

Applied across all wrappers with the pattern: pyrocmsmi, pyamdsmi, pynvml,
pydcmi, pymtml, pyhgml, pyixml, pymxsml.