refactor: move modules to common folder since separation was unsound

STRUCTURE.md

@@ -26,13 +26,11 @@ Make sure to utilize the github search if you know what you need!
     These just add configuration unconditionally and don't expose any further options.
   - `modules/optional/` contains configuration that is only needed sometimes, and which should
     be included explicitly by hosts that require it.
-  - `modules/meta/` contains meta-modules that simplify the option interface of existing options.
+  - `modules/*` contains regular modules and meta-modules that simplify the option interface of existing options.
     I use this for stuff that I don't need on all my hosts and that may require different settings
     for each host while sharing a common basis.
     Some of these are "meta" in the sense that they depend on their own definitions on multiple hosts (wireguard).
     These are probably as opinionated as stuff in `modules/config/` but may be a little more general.
-    The `wireguard` module would even be a candidate for extraction to a separate flake, together with the related apps.
-  - `modules/*/` regular modules related to <xyz>, similar structure as in `nixpkgs/nixos/modules`
 
 - `nix/` library functions and flake plumbing
   - `generate-installer-package.nix` Helper package that that will be available in our iso images. This provides the `install-system` command that will do a full install including partitioning.

modules/default.nix

@@ -27,25 +27,20 @@
 
     ./guests
 
-    # TODO merge as ./*
-    ./meta/kanidm.nix
-    ./meta/nginx.nix
-    ./meta/oauth2-proxy.nix
-    ./meta/promtail.nix
-    ./meta/telegraf.nix
-    ./meta/wireguard.nix
-    ./meta/wireguard-proxy.nix
-
-    ./networking/interface-naming.nix
-    ./networking/provided-domains.nix
-
-    ./repo/distributed-config.nix
-    ./repo/meta.nix
-    ./repo/secrets.nix
-
-    ./security/acme-wildcard.nix
-
-    ./system/deterministic-ids.nix
+    ./acme-wildcard.nix
+    ./deterministic-ids.nix
+    ./distributed-config.nix
+    ./interface-naming.nix
+    ./kanidm.nix
+    ./meta.nix
+    ./nginx.nix
+    ./oauth2-proxy.nix
+    ./promtail.nix
+    ./provided-domains.nix
+    ./secrets.nix
+    ./telegraf.nix
+    ./wireguard-proxy.nix
+    ./wireguard.nix
   ];
 
   nixpkgs.overlays = [