feat(resources): bundle color themes and compiled xterm-ghostty terminfo

Makes the resources directory self-contained like Ghostty's share/ghostty:
- themes/: the 463 iTerm2-Color-Schemes themes Ghostty 1.3.1 ships
  (release 20260216-151611-fc73ce3), with the upstream MIT license.
- terminfo/: xterm-ghostty compiled with `tic -x` from the terminfo
  source generated by ghostty-termio; `infocmp -x` is identical to the
  installed Ghostty's entry.

The generator script and resources-dir discovery changes follow in a
separate commit.

Test Plan:
- TERMINFO=resources/terminfo infocmp -x xterm-ghostty

resources/themes/Challenger Deep

@@ -0,0 +1,22 @@
+palette = 0=#141228
+palette = 1=#ff5458
+palette = 2=#62d196
+palette = 3=#ffb378
+palette = 4=#65b2ff
+palette = 5=#906cff
+palette = 6=#63f2f1
+palette = 7=#a6b3cc
+palette = 8=#565575
+palette = 9=#ff8080
+palette = 10=#95ffa4
+palette = 11=#ffe9aa
+palette = 12=#91ddff
+palette = 13=#c991e1
+palette = 14=#aaffe4
+palette = 15=#cbe3e7
+background = #1e1c31
+foreground = #cbe1e7
+cursor-color = #fbfcfc
+cursor-text = #ff271d
+selection-background = #cbe1e7
+selection-foreground = #1e1c31