fix: Upgrade capnp to 0.24 (#11656)
## Summary
- Upgrades capnp from 0.17.2 to 0.24
- Upgrades capnpc from 0.18.0 to 0.24
- Fixes RUSTSEC-2025-0143 (unsound APIs in constant::Reader and
StructSchema)
<sub>CLOSES TURBO-5179</sub>
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Co-authored-by: Copilot <198982749+Copilot@users.noreply.github.com>
