feat: Signals API

[logan-gatlin]

Added the Signal struct which represents and interprets signals received by the runtime. Currently, signals require compiling with "panic=unwind", and are not supported in miniflare. I added the tests anyway, including a new test suite for panic=unwind tests as I presume we will want to write more of those in the future. The example code I added is deployed here: https://pi.logan.md/, confirming that the new API does work in production. We may want to wait for miniflare to catch up and signal support for panic=abort to land before merging this.

This PR bumps most of our dependencies by a significant amount which is something to keep in mind.

[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.

✅ 2 untouched benchmarks

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_{Comparing logan/signal-test (a506eb4) with main (652cd4b)}