intel-gpu: pin unsloth_zoo>=2026.5.2 via huggingfacenotorch (#5499)

Fixes unslothai/unsloth#5494: installing any intel-gpu-torch* extra
without also pulling `huggingface` or `colab-new` lets the resolver
silently fall back to a stale unsloth_zoo (2026.3.6 in the original
report) because no version floor is enforced on
`unsloth_zoo[intelgpu]` in those blocks.

unsloth_zoo 2026.5.2 (just released) also relaxes its own torch upper
bound from <2.11.0 to <2.13.0, which is what unblocks the resolver for
the intel-gpu-torch2110 and intel-gpu-torch2120 extras shipped in
#5484.

Adding the floor in `huggingfacenotorch` propagates it to every
extra that includes the HF-without-torch base: amd, huggingface, and
all nine intelgputorch* blocks. Single line, single source of truth.

Requires unsloth_zoo 2026.5.2 to be on PyPI for end-to-end resolution.

pyproject.toml

@@ -69,6 +69,7 @@ triton = [
 ]
 
 huggingfacenotorch = [
+    "unsloth_zoo>=2026.5.2",
     "wheel>=0.42.0",
     "packaging",
     "numpy",