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/my-base16-palette.el

@@ -18,7 +18,7 @@
     "#3A9C36")) ; green: 绿色
 
 (defvar my-base16-light-core-palette
-  '("#062617"   ; darkest-base: 最深背景
+  '("#062624"   ; darkest-base: 最深背景
     "#E3FFE6"   ; brightest-base: 最亮前景
     "#A87C04"   ; yellow: 黄色
     "#C24713"   ; orange: 橙色