actually add the magic-foldr nix-thunk

obelisk/dep/magic-foldr/default.nix

+# DO NOT HAND-EDIT THIS FILE
+import (import ./thunk.nix)
\ No newline at end of file

obelisk/dep/magic-foldr/git.json

+{
+  "url": "https://whetstone.private.storage/PrivateStorage/magic-foldr",
+  "rev": "4920e071a4f271470aa31fb27196f5f7092bcebd",
+  "sha256": "0n3zj7bph4g071naaym4w69h9b8ajxrxafqmazq9dcq3n9fyps1y",
+  "private": false,
+  "fetchSubmodules": false,
+  "branch": "1.parse-collective"
+}

obelisk/dep/magic-foldr/thunk.nix

+# DO NOT HAND-EDIT THIS FILE
+let fetch = {url, rev, branch ? null, sha256 ? null, fetchSubmodules ? false, private ? false, ...}:
+  let realUrl = let firstChar = builtins.substring 0 1 url; in
+    if firstChar == "/" then /. + url
+    else if firstChar == "." then ./. + url
+    else url;
+  in if !fetchSubmodules && private then builtins.fetchGit {
+    url = realUrl; inherit rev;
+    ${if branch == null then null else "ref"} = branch;
+  } else (import (builtins.fetchTarball {
+  url = "https://github.com/NixOS/nixpkgs/archive/3aad50c30c826430b0270fcf8264c8c41b005403.tar.gz";
+  sha256 = "0xwqsf08sywd23x0xvw4c4ghq0l28w2ki22h0bdn766i16z9q2gr";
+}) {}).fetchgit {
+    url = realUrl; inherit rev sha256;
+  };
+  json = builtins.fromJSON (builtins.readFile ./git.json);
+in fetch json
\ No newline at end of file