Debug startup, support LSP, update KBDs

Debug startup:
- some packages were missing explicit use-package calls, which made this
  configuration incompatible with fresh computers. After crashing my MBP
  and trying to get this working thereafter, I learned.

Support LSP:
- LSP support for Haskell is good; embrace and prefer over Intero

Update KBDs:
- preferences change
- changing to a light theme (for now)

emacs.d/snippets/haskell-mode/derive-safe-copy

@@ -0,0 +1,5 @@
+# -*- mode: snippet -*-
+# name: Derive Safe Copy
+# key: dsc
+# --
+deriveSafeCopy 0 'base ''$1