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

init.el

@@ -9,9 +9,7 @@
 	         (expand-file-name (concat user-emacs-directory "lisp")))
 
 (setq custom-file (expand-file-name "custom.el" user-emacs-directory))
-
-(when (file-exists-p custom-file)
-  (load-file custom-file))
+(load custom-file t)
 
 (require 'init-const)
 
@@ -32,7 +30,8 @@
       (require 'init-ui)
       (require 'init-kbd-func)
       (require 'init-kbd)
-      (require 'init-segmentation))
+      (require 'init-segmentation)
+      (load "init-local" t))
   (progn
     (require 'init-terminal-startup)
     (load "init-proxy" t)