chore: Significantly restructure folder layout

This moves the various projects from "type-based" folders (such as
"services" or "tools") into more appropriate semantic folders (such as
"nix", "ops" or "web").

Deprecated projects (nixcon-demo & gotest) which only existed for
testing/demonstration purposes have been removed.

(Note: *all* builds are broken with this commit)

ops/infra/nixos/stallo-configuration.nix

@@ -0,0 +1,39 @@
+# Local configuration for 'stallo' (Home desktop PC)
+{ config, pkgs, ...}:
+
+{
+  boot.initrd.luks.devices.stallo-luks.device = "/dev/disk/by-uuid/b484cf1e-a27b-4785-8bd6-fa85a004b073";
+
+  # Use proprietary nvidia driver
+  services.xserver.videoDrivers = [ "nvidia" ];
+
+  # Enable 32-bit compatibility for Steam:
+  hardware.opengl.driSupport32Bit = true;
+  hardware.pulseaudio.support32Bit = true;
+
+  # Wine for Blizzard stuff
+  environment.systemPackages = with pkgs.unstable; [ wineWowPackages.staging winetricks ];
+
+  networking = {
+    hostName = "stallo";
+    wireless.enable = true;
+    wireless.networks = {
+      # Welcome to roast club!
+
+      "How do I computer fast?" = {
+        psk = "washyourface";
+        # Prefer 5Ghz unless the card is acting up.
+        priority = 10;
+      };
+
+      "How do I computer?" = {
+        psk = "washyourface";
+      };
+    };
+    # IPv6 at home, of course:
+    nameservers = [
+      "2606:4700:4700::1111"
+      "2606:4700:4700::1001"
+    ];
+  };
+}