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)

fun/gemma/frontend/elm-package.json

@@ -0,0 +1,17 @@
+{
+    "version": "1.0.0",
+    "summary": "helpful summary of your project, less than 80 characters",
+    "repository": "https://github.com/user/project.git",
+    "license": "BSD3",
+    "source-directories": [
+        "."
+    ],
+    "exposed-modules": [],
+    "dependencies": {
+        "elm-lang/core": "5.1.1 <= v < 6.0.0",
+        "elm-lang/html": "2.0.0 <= v < 3.0.0",
+        "elm-lang/http": "1.0.0 <= v < 2.0.0",
+        "debois/elm-mdl": "8.1.0 <= v < 9.0.0"
+    },
+    "elm-version": "0.18.0 <= v < 0.19.0"
+}