feat: add commands to get and update root encryption key

[sweatybridge]

What kind of change does this PR introduce?

feature

What is the new behavior?

Syncs linked project's root encryption key to another new project

supabase vault get-root-key | supabase vault update-root-key --project <new_project_ref>

Additional context

Add any other context or screenshots.

[coveralls]

Pull Request Test Coverage Report for Build 6376940149

• 6 of 36 (16.67%) changed or added relevant lines in 3 files are covered.
• 5 unchanged lines in 1 file lost coverage.
• Overall coverage decreased (-0.2%) to 56.598%

---

Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
cmd/rootKey.go	6	12	50.0%
internal/root_key/get/get.go	0	10	0.0%
internal/root_key/update/update.go	0	14	0.0%

Files with Coverage Reduction	New Missed Lines	%
internal/gen/keys/keys.go	5	12.31%

Totals
Change from base Build 6375785582:	-0.2%
Covered Lines:	5018
Relevant Lines:	8866

---

💛 - Coveralls

[soedirgo]

This is specifically pgsodium root key though - might be worth qualifying that?

[sweatybridge]

This is specifically pgsodium root key though - might be worth qualifying that?

I thought about that but didn't want to mention the name of extensions in cli command, due to the risk of future compatibility issues like extension renaming or deprecation.

How about supabase vault get-root-key because it aligns with our product offering and is less likely to change.

[soedirgo]

Yeah sgtm