sccache cleanup

[AdamGS]

Rationale for this change

Make better use of sccache across our GH actions workflows.

What changes are included in this PR?

1. Makes sccache opt in
2. When sccache is used, make sure its properly configured with runs-on.

What APIs are changed? Are there any user-facing changes?

None

[0ax1]

Why should this not be turned on by default?

[0ax1]

curious about a 2nd opinion here. @robert3005

[codspeed-hq]

Merging this PR will improve performance by 11.98%

⚠️ Unknown Walltime execution environment detected

Using the Walltime instrument on standard Hosted Runners will lead to inconsistent data.

For the most accurate results, we recommend using CodSpeed Macro Runners: bare-metal machines fine-tuned for performance measurement consistency.

⚡ 5 improved benchmarks
✅ 1640 untouched benchmarks
⏩ 4 skipped benchmarks¹

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
⚡	Simulation	bitwise_not_vortex_buffer_mut[128]	244.4 ns	215.3 ns	+13.55%
⚡	Simulation	chunked_varbinview_into_canonical[(100, 100)]	306.9 µs	272.1 µs	+12.81%
⚡	Simulation	chunked_varbinview_opt_canonical_into[(100, 100)]	340.6 µs	305.4 µs	+11.53%
⚡	Simulation	rebuild_naive	101.9 µs	91.4 µs	+11.47%
⚡	Simulation	bitwise_not_vortex_buffer_mut[1024]	304.7 ns	275.6 ns	+10.58%

Tip

Curious why this is faster? Comment @codspeedbot explain why this is faster on this PR, or directly use the CodSpeed MCP with your agent.

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_{Comparing adamg/sccache-pass (33d6b69) with develop (e6c312a)}

Footnotes

1. 4 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

[0ax1]

in the name of consistency.

[AdamGS]

c/cpp runs into some issues with our cmakelists, will fix in a followup.