feat: support encrypted values in config

[sweatybridge]

What kind of change does this PR introduce?

feature

What is the new behavior?

Follow dotenvx convention for encrypted secrets.

api_key = "encrypted:<base64_encoded>"

Additional context

Add any other context or screenshots.

[coveralls]

Pull Request Test Coverage Report for Build 12703005375

Details

• 116 of 258 (44.96%) changed or added relevant lines in 6 files are covered.
• 14 unchanged lines in 4 files lost coverage.
• Overall coverage decreased (-0.2%) to 58.616%

---

Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
internal/config/push/push.go	0	2	0.0%
pkg/config/config.go	26	34	76.47%
internal/start/start.go	1	12	8.33%
pkg/config/auth.go	40	161	24.84%

Files with Coverage Reduction	New Missed Lines	%
pkg/config/config.go	1	53.96%
internal/storage/rm/rm.go	2	89.53%
internal/gen/keys/keys.go	5	12.9%
pkg/config/auth.go	6	58.85%

Totals
Change from base Build 12687685954:	-0.2%
Covered Lines:	7616
Relevant Lines:	12993

---

💛 - Coveralls