[water7] feat: Add sops + age secret handling, still wip

I'm kinda lost, but we'll get there lol soon forgejo secrets will be fixed!

Signed-off-by: SindreKjelsrud <sindre@kjelsrud.dev>

flake.lock

@@ -61,9 +61,30 @@
       "inputs": {
         "home-manager": "home-manager",
         "nixpkgs": "nixpkgs",
+        "sops-nix": "sops-nix",
         "zen-browser": "zen-browser"
       }
     },
+    "sops-nix": {
+      "inputs": {
+        "nixpkgs": [
+          "nixpkgs"
+        ]
+      },
+      "locked": {
+        "lastModified": 1760240450,
+        "narHash": "sha256-sa9bS9jSyc4vH0jSWrUsPGdqtMvDwmkLg971ntWOo2U=",
+        "owner": "mic92",
+        "repo": "sops-nix",
+        "rev": "41fd1f7570c89f645ee0ada0be4e2d3c4b169549",
+        "type": "github"
+      },
+      "original": {
+        "owner": "mic92",
+        "repo": "sops-nix",
+        "type": "github"
+      }
+    },
     "zen-browser": {
       "inputs": {
         "home-manager": "home-manager_2",