Vendor libs/hump, sfxrlua, json4lua, narrator as real files

These were committed as empty submodule gitlinks with no .gitmodules,
so the folders were never populated and the game could not load
(require of libs/hump/timer, libs/sfxrlua/sfxr, narrator.narrator).
Checked out each at its pinned commit and vendored the files, matching
the existing bundled-libs convention. Removed the junk libs/libs/ tree.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

libs/narrator/test/units/labels-nested.ink

@@ -0,0 +1,22 @@
+-> dialog_start
+==dialog_start==
+
+* [Tell me about the mister]
+- - (dima)
+- - His name is Dima.
+* * {not vika} [Tell me about Vika]
+      -> vika
+* * [Finish conversation]
+      -> stop_dialog
+
+* [Tell me about the missis]
+- - (vika)
+  Her name is Vika.
+* * {not dima} [Tell me about Dima]
+      -> dima
+* * [Finish conversation]
+      -> stop_dialog
+
+==stop_dialog==
+That's all.
+-> END