chore(config): Refactor Emacs configuration with multiple improvements

- Replace projectile with built-in project.el
- Add cal-china-x for Chinese lunar calendar support
- Add dired-gitignore integration with dirvish
- Add mwim for smarter line navigation
- Add keycast mode for key display
- Add ef-themes theme collection
- Improve corfu terminal handling for Emacs 31+
- Add gptel-agent-project and consult-ripgrep-project helpers
- Remove custom.el from repo, support init-local.el for local config
- Update theme faces for transient, keycast, and calendar holidays
- Various keybinding additions and cleanup

lisp/init-window.el

@@ -25,6 +25,7 @@
           "\\*Backtrace\\*"
           "\\*prodigy\\*"
           "\\*Calendar\\*"
+          "\\*Holidays\\*"
           "\\*Embark Actions\\*"
           "\\*Finder\\*"
           "\\*Kill Ring\\*"
@@ -54,6 +55,7 @@
 	  ibuffer-mode
 
           "^\\*eshell.*\\*.*$" eshell-mode
+	  ".*eshell\\*$"
           "^\\*shell.*\\*.*$"  shell-mode
           "^\\*terminal.*\\*.*$" term-mode
           "^\\*vterm.*\\*.*$"  vterm-mode