move getrandom backend override to config.toml

[onursatici]

Summary

to compile the wasm target we need to override the getrandom backend to be unsupported. We were previously doing this in CI, but for local builds that override was not picked up.

[codspeed-hq]

Merging this PR will not alter performance

⚠️ 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.

⚡ 1 improved benchmark
❌ 3 regressed benchmarks
✅ 1217 untouched benchmarks

Warning

Please fix the performance issues or acknowledge them on CodSpeed.

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
❌	Simulation	chunked_varbinview_canonical_into[(100, 100)]	273.3 µs	308 µs	-11.28%
⚡	Simulation	chunked_varbinview_opt_canonical_into[(1000, 10)]	225.3 µs	188 µs	+19.84%
❌	Simulation	new_alp_prim_test_between[f32, 16384]	103.8 µs	118.3 µs	-12.27%
❌	Simulation	new_alp_prim_test_between[f32, 32768]	153.2 µs	182.1 µs	-15.87%

Tip

Investigate this regression by commenting @codspeedbot fix this regression on this PR, or directly use the CodSpeed MCP with your agent.

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_{Comparing os/web-fix-compile (058d0fb) with develop (bf1527e)}