v0.4.50

What's Changed

• chore: move nightly cron into 03:XX UTC window (Phase A.7.2) by @vampik33 in #49
• ci: gate crates.io publish on successful release-binaries by @vampik33 in #51
• ci: add scheduled-failure catch-all Slack notifier by @vampik33 in #53
• chore(ci): wire branch-invariants reusable into this repo by @vampik33 in #59
• chore: sync toolchain config from canonical source by @vampik33 in #61
• Use stable provider registry defaults by @grishkyan in #63

Full Changelog: v0.4.49...v0.4.50