chore(main): release 3.12.0

:robot: I have created a release *beep* *boop* --- ## [3.12.0](https://github.com/rest-nvim/rest.nvim/compare/v3.11.2...v3.12.0) (2025-03-08) ### Features * add default = true for highlight groups definition. ([#541](https://github.com/rest-nvim/rest.nvim/issues/541)) ([54ee52a](https://github.com/rest-nvim/rest.nvim/commit/54ee52ab94ff52055259b79d3aef5311913f0c5f)) ### Bug Fixes * Statistics syntax highlight ([#540](https://github.com/rest-nvim/rest.nvim/issues/540)) ([7ca9204](https://github.com/rest-nvim/rest.nvim/commit/7ca92042e0f0fa78bccb929782e542bff827bf74)) --- This PR was generated with [Release Please](https://github.com/googleapis/release-please). See [documentation](https://github.com/googleapis/release-please#release-please).