chore: add tasksets/harnesses to exclude-newer ignore list

[eexwhyzee]

Note

Low Risk
Dependency resolver configuration only; no application or security logic changes.

Overview
Adds tasksets and harnesses to the uv exclude-newer-package allowlist in pyproject.toml (and the matching block in uv.lock), alongside other first-party packages like verifiers and renderers.

Setting them to false opts those packages out of the global 7-day exclude-newer cap so newer PrimeIntellect releases can be resolved without waiting for the cooldown window.

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