chore!: Introduce ZITADEL v3 (#9645)

This PR summarizes multiple changes specifically only available with
ZITADEL v3:

- feat: Web Keys management
(https://github.com/zitadel/zitadel/pull/9526)
- fix(cmd): ensure proper working of mirror
(https://github.com/zitadel/zitadel/pull/9509)
- feat(Authz): system user support for permission check v2
(https://github.com/zitadel/zitadel/pull/9640)
- chore(license): change from Apache to AGPL
(https://github.com/zitadel/zitadel/pull/9597)
- feat(console): list v2 sessions
(https://github.com/zitadel/zitadel/pull/9539)
- fix(console): add loginV2 feature flag
(https://github.com/zitadel/zitadel/pull/9682)
- fix(feature flags): allow reading "own" flags
(https://github.com/zitadel/zitadel/pull/9649)
- feat(console): add Actions V2 UI
(https://github.com/zitadel/zitadel/pull/9591)

BREAKING CHANGE
- feat(webkey): migrate to v2beta API
(https://github.com/zitadel/zitadel/pull/9445)
- chore!: remove CockroachDB Support
(https://github.com/zitadel/zitadel/pull/9444)
- feat(actions): migrate to v2beta API
(https://github.com/zitadel/zitadel/pull/9489)

---------

Co-authored-by: Livio Spring <[email protected]>
Co-authored-by: Stefan Benz <[email protected]>
Co-authored-by: Silvan <[email protected]>
Co-authored-by: Ramon <[email protected]>
Co-authored-by: Elio Bischof <[email protected]>
Co-authored-by: Kenta Yamaguchi <[email protected]>
Co-authored-by: Harsha Reddy <[email protected]>
Co-authored-by: Livio Spring <[email protected]>
Co-authored-by: Max Peintner <[email protected]>
Co-authored-by: Iraq <[email protected]>
Co-authored-by: Florian Forster <[email protected]>
Co-authored-by: Tim Möhlmann <[email protected]>
Co-authored-by: Copilot <[email protected]>
Co-authored-by: Max Peintner <[email protected]>

.github/pull_request_template.md

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