Nightly build 2024.09.20

What's Changed

Proposals accepted and merged 📜

• Lambdas by @CJ-Johnson in #3848

Toolchain and implementation changes 🛠️

• Support initialization of specific classes from struct literals by @zygoloid in #4320
• Iterate on diagnostic structure by @jonmeow in #4321
• Add usage tips to NOAUTOUPDATE tests by @geoffromer in #4324
• Update basic diagnostic capitalization/punctuation by @jonmeow in #4328
• Adopt new diagnostic conventions in handle_class.cpp by @zygoloid in #4327

Documentation changes 📝

• Fix singular/plural mismatch in design README by @josh11b in #4326

Other changes

• Bump google-protobuf from 4.27.3 to 4.27.5 in /website in the bundler group across 1 directory by @dependabot in #4325

Full Changelog: v0.0.0-0.nightly.2024.09.19...v0.0.0-0.nightly.2024.09.20