feat: add supabase unlink command

[eleijonmarck]

NOTE:

• tests are not ready yet, first I want confirmation that I am heading in the right direction.

What kind of change does this PR introduce?

This introduces a new unlink cmd that unlinks the project set.

What is the current behavior?

We have no way of "unlinking" a project today. This PR makes it so that we clean the .temp file from project-refs.

https://github.com/orgs/supabase/discussions/17991

What is the new behavior?

(2) ~/dev/supabase/cli on main
% go run . link
Selected project ref: <project-ref>
Enter your database password (or leave blank to skip):
Finished supabase link.
(base)
(2) ~/dev/supabase/cli on main took 5s
% go run . unlink
Finished supabase unlink.

cleaned up the .temp files from project-refs with empty string.

(2) ~/dev/supabase/cli/supabase on main
% cd .temp
(base)
(2) ~/dev/supabase/cli/supabase/.temp on main
% ls
gotrue-version  pooler-url  postgres-version  project-ref  rest-version  storage-version
(base)
(2) ~/dev/supabase/cli/supabase/.temp on main
% cat rest-version
(base)
(2) ~/dev/supabase/cli/supabase/.temp on main
% cat project-ref
(base)

Additional context

Add any other context or screenshots.

[sweatybridge]

Thank you for the contribution. This would be a much appreciated feature.

In addition to cleaning the .temp files, we should also purge any saved credentials from the platform native credentials store.

[coveralls]

Pull Request Test Coverage Report for Build 7691362763

• -6 of 24 (75.0%) changed or added relevant lines in 2 files are covered.
• 5 unchanged lines in 1 file lost coverage.
• Overall coverage increased (+0.008%) to 58.763%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
internal/unlink/unlink.go	15	17	88.24%
cmd/unlink.go	3	7	42.86%

Files with Coverage Reduction	New Missed Lines	%
internal/gen/keys/keys.go	5	11.76%

Totals
Change from base Build 7690958697:	0.008%
Covered Lines:	6159
Relevant Lines:	10481

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💛 - Coveralls

[eleijonmarck]

@sweatybridge update the tests to confirm and i think this works for me when I unlink using supabase now. Could you test out to unlink a project

[sweatybridge]

I made some changes to handle missing keys in WSL environments. Thanks for the contribution!