1.5.0: OBS 32+ and Fix deb packages

• OBS 32 or later is required from version 1.5.0
• A first-run About dialog is shown after installation or update
• Debian and Ubuntu packaging has been overhauled
• INSTALL.html is included in the Windows ZIP

What's Changed

• Bump actions/attest from 4.1.1 to 4.2.0 by @dependabot[bot] in #926
• Bump actions/setup-node from 6.4.0 to 7.0.0 by @dependabot[bot] in #927
• Bump actions/checkout from 7.0.0 to 7.0.1 by @dependabot[bot] in #928
• Update CI, dependencies and pages by @umireon in #940
• Fix CI errors by @umireon in #941
• Fix GPU support again by @umireon in #942
• Add build-plugin-macos.yml by @umireon in #944
• Bump actions/attest from 4.2.0 to 4.2.2 by @dependabot[bot] in #946
• Refactor build workflows by @umireon in #949
• Improve self-service support by @umireon in #951
• Bump actions/setup-python from 6.3.0 to 7.0.0 by @dependabot[bot] in #929
• Add download buttons by @umireon in #952
• Update OBS deps to 32.2.1 by @umireon in #954
• Add a new download trends chart by @umireon in #956
• Add star-history.svg by @umireon in #957
• Bump actions/attest from 4.2.0 to 4.2.2 by @dependabot[bot] in #958
• Add start-up about dialog with refactored version check by @umireon in #961
• Add GUI tests on Windows by @umireon in #962
• Bump version to 1.5.0 by @umireon in #970
• Assert the depth instead of the full model dtype by @bxdxnn in #972
• Fix release process by @umireon in #973
• Tidy up release artifacts by @umireon in #975
• Add skip-decompress for handling zip on Release CD by @umireon in #976
• Fix Release CD again (artifact names and bundle id) by @umireon in #977