Generate Auth Keys

Added the ability to generate new auth keys. Can see in the tailscale
logs that new keys are being generated with a 90 day expiration time.
This should be enough to close out issue #7.

Cargo.toml

@@ -4,6 +4,7 @@ version = "0.1.0"
 edition = "2021"
 
 [dependencies]
-http = "1.2.0"
 oauth2 = "4.4.2"
+reqwest = { version = "0.12.9", features = ["blocking"] }
+serde = "1.0.216"
 serde_json = "1.0.133"