feat(virtualcam): add Google OAuth, enable Shkeeper payments, update Caddy rules

- Update virtualcam website and API to latest repository revisions.
- Add Google OAuth client ID and secrets decryption for Google auth.
- Enable Shkeeper BTC/USD payment processing (`BYPASS_PAYMENTS=false`) and add service dependencies.
- Update Caddy `admin_gate` IP access rules and remove redundant `admin_gate` import from app proxy.
- Configure weekly automatic Nix garbage collection (`--delete-older-than 14d`) and nix store optimization.

servers/hetzner/secrets/secrets.yaml

@@ -1,3 +1,4 @@
+shkeeper_api_key: ENC[AES256_GCM,data:kUymtefYJOllK5cxKHhD3HnXO/uo1w==,iv:OH9ZaQJZsFfo00BIl5MlRw1XBzHUmFi1FW54/J6O/8Q=,tag:HQJyuEoz5fsDi7iMq3PEzw==,type:str]
 restic_password: ENC[AES256_GCM,data:OHQlxUpNnTqMQm6A/o3ID/3F91NpVKOrsFYdLqrtI4vp+6TWHR8=,iv:bBd+gfi78lgTaTv0QUWYGQWPsurrzx90VvOzA2d2euA=,tag:qsHSdAHx1auwdZCgn2O5Qw==,type:str]
 b2_key_id: ENC[AES256_GCM,data:4B9rvg06baH6aNiT,iv:Qk1ToF3lMYLTrZdzpfaoGVzdiKYs492w9fzn4/TbNfQ=,tag:djxfqwgNZmRGqvteTX9G3w==,type:str]
 b2_application_key: ENC[AES256_GCM,data:xGAbBqx+6ErK7sy3FR0yza6mJU5oc5uQQGcwKtcPp1Ef4XEVd8do/wN7,iv:CojcoykDRBfvN8yqMMrPJq9mtAwxyswqXXVBKPupxDs=,tag:BkfFHAGJvtCDUpFoxXVP3Q==,type:str]
@@ -7,6 +8,7 @@ virtualcam_license_signing_key: ENC[AES256_GCM,data:zk8YDER9d9mBOdXgEKKC6dubSMfz
 virtualcam_admin_token: ENC[AES256_GCM,data:JC5zSFBCoEapxv/Kcs4VXk3HAkiqwXVrCv1rlqFsXVx3LGspnQdzjOIahlM=,iv:GRVfMNGkwC3xXR00ww29rFbhTrpuViad+H05yDhR9BA=,tag:OBnxBD/8KU4mn17FFTcdng==,type:str]
 git_ssh_key_b64: ENC[AES256_GCM,data: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,iv:cbIpwwhmyJVvvTMB95YBzt+RQLOji6yJh+SpcJc3Q1Y=,tag:t8WxU1IPDfkB8muTdBLUhg==,type:str]
 virtualcam_smtp_pass: ENC[AES256_GCM,data:D5kDTQP9/YV5BjAWeTn0G2zKe+s=,iv:7dZJprrs0S2ECtbDQuvhUWsU0Xzpld5/XZqdbyefg0o=,tag:uWe811KAisBJ5M1EhJjrcQ==,type:str]
+virtualcam_google_OAuth_secret: ENC[AES256_GCM,data:kPJIP4iH2vFo+VRojvhjzrQhDWidFq7kjC7ZaFcwJ7dNHlo=,iv:qKWClwSIRPU2Xz50bGYqU+eMR/iFxqnaKkb18eL3aMU=,tag:78jGQgL1myDBMiZP8GZ80g==,type:str]
 sops:
     kms: []
     gcp_kms: []
@@ -40,8 +42,8 @@ sops:
             MHJrVVpDYWdJNmxtUkozSzR4Nmt3R28KrhYi830HUFAPfg8WvPad7BAuNe1mYOWt
             WEFIquuX/H/N+y/7uQcBDbvnBzyropE1hW8aNrxSKMeawvQZWNXkZA==
             -----END AGE ENCRYPTED FILE-----
-    lastmodified: "2026-08-15T15:47:14Z"
-    mac: ENC[AES256_GCM,data:I28P0NVocgflBTd27KrVOV2Nh5cUpuv8yL13Z54dFron3g27j0sr5PJMc7ZzTkHvKrU+gwBxPBmldh/q3QB50Mz3bK4S3b8O5hPp7xR4mc3ajQwMPaqLj7A6aeXsixIQVDfZEHtXpWB4DKaA8FLYKOZBAXhW2f1SGWnVJwKqn9M=,iv:fMlP/VxGN3y+d0unBA87qfUaT51MIQsAKsuEXTv3qDg=,tag:yjaSL1ymvdpGDuy7OdANZA==,type:str]
+    lastmodified: "2026-08-19T10:30:19Z"
+    mac: ENC[AES256_GCM,data:JOWFguh2iE4+OyU00l+2gn7GWv2yej37OLLhVVO6Yb7Kv4vgk4NhZKJLqopteQK1o6dPeWbeIydHG1Qmef0Sm0NmCyi7i6BCTplVizf/puaGjpkU5YAs90+HiEa9cKlNQ5brfNH3YecJeN9dK+d7o8bMO/xPv3raqFMBBoVtgu4=,iv:A7kCOzyWwiVaXKVMKXQ4j86zz2f65wAjOtaVEuLa81I=,tag:bcbPsmRRFRHX7qi4WdYb0g==,type:str]
     pgp: []
     unencrypted_suffix: _unencrypted
     version: 3.8.1