chore: add deb/rpm

[tianzhou]

Fix #61

[Copilot]

Pull Request Overview

This PR adds DEB and RPM package generation to the GitHub Actions release workflow to address package distribution requirements. The changes introduce a new packaging job that creates Linux distribution packages using nfpm (a simple package manager for creating packages).

• Adds a new packages job that generates DEB and RPM packages for Linux AMD64
• Updates the release job to depend on both build and packages jobs
• Includes the generated packages in the GitHub release artifacts

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[Copilot]

Using [trusted=yes] bypasses GPG verification for the repository, which poses a security risk. Consider adding the GPG key verification or using the official installation method.

Suggested change

	echo "deb [trusted=yes] https://repo.goreleaser.com/apt/ /" | sudo tee /etc/apt/sources.list.d/goreleaser.list
	curl -fsSL https://repo.goreleaser.com/gpg.key | sudo gpg --dearmor -o /usr/share/keyrings/goreleaser-archive-keyring.gpg
	echo "deb [signed-by=/usr/share/keyrings/goreleaser-archive-keyring.gpg] https://repo.goreleaser.com/apt/ /" | sudo tee /etc/apt/sources.list.d/goreleaser.list

[Copilot]

The artifact paths reference 'binaries/' directory but the packages job uploads artifacts with names 'pgschema-deb' and 'pgschema-rpm'. The correct paths should be 'pgschema-deb/.deb' and 'pgschema-rpm/.rpm'.