backstage release v3.0.0

Added

• (agent-platform) [breaking] Agent Platform shell — the new portal UI in #2899 by @Rotfuks

Changed

• Align files according to platform standards in #2941 by @giantswarm-align-files[bot]
• Align files according to platform standards in #2942 by @giantswarm-align-files[bot]
• (deps) Update dependency @lezer/highlight to v1.2.5 in #2943 by @renovate[bot]
• (deps) Update ai-sdk packages in #2944 by @renovate[bot]

Fixed

• (bot-prs) Report a GitHub rate limit once, with its reset, and hold marge calls until then in #2939 by @QuentinBisson
• (deps) Update dependency @giantswarm/semver-ts to v0.2.4 in #2895 by @renovate[bot]

Full Changelog: https://github.com/giantswarm/backstage/compare/v2.97.0...v3.0.0