Fix CUA mode, selection keybindings, and replace Corfu with Company

Major improvements to Emacs configuration:

1. Fixed CUA mode and C-Shift-Arrow selection issues
   - Properly configured CUA mode for copy/paste (C-c, C-v, C-x)
   - Fixed C-Shift-Arrow word selection that was being intercepted
   - Added mode-specific CUA disabling for special modes

2. Replaced Corfu with Company mode
   - Removed problematic Corfu configuration causing errors
   - Installed and configured Company for stable auto-completion
   - Set up proper completion triggers and navigation

3. Integrated standalone fix files into existing configuration
   - Merged keybinding-fix.el into relevant config files
   - Added diagnostic functions for debugging keybinding issues
   - Cleaner organization with fixes in their respective modules

4. Enhanced diagnostics
   - Added diagnose-cua-selection for CUA/selection issues
   - Added diagnose-key-conflicts for debugging key bindings
   - Emergency editing restoration functions preserved

All changes tested and verified working.

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

lisp/elfeed-config.el

@@ -181,12 +181,28 @@
 
 ;; Keybindings for elfeed
 (with-eval-after-load 'elfeed
+  ;; Disable CUA mode in elfeed buffers to allow single-key commands
+  (add-hook 'elfeed-search-mode-hook
+            (lambda ()
+              (setq-local cua-mode nil)
+              (setq-local cua-enable-cua-keys nil)))
+  
+  (add-hook 'elfeed-show-mode-hook
+            (lambda ()
+              (setq-local cua-mode nil)
+              (setq-local cua-enable-cua-keys nil)))
+  
+  ;; Define keybindings
   (define-key elfeed-search-mode-map (kbd "j") 'next-line)
   (define-key elfeed-search-mode-map (kbd "k") 'previous-line)
   (define-key elfeed-search-mode-map (kbd "m") 'elfeed-search-toggle-all-star)
   (define-key elfeed-search-mode-map (kbd "u") 'elfeed-search-toggle-all-unread)
   (define-key elfeed-search-mode-map (kbd "U") 'elfeed-update-async)
-  (define-key elfeed-search-mode-map (kbd "f") 'elfeed-search-live-filter))
+  (define-key elfeed-search-mode-map (kbd "f") 'elfeed-search-live-filter)
+  (define-key elfeed-search-mode-map (kbd "g") 'elfeed-search-update--force)
+  (define-key elfeed-search-mode-map (kbd "G") 'elfeed-search-fetch)
+  (define-key elfeed-search-mode-map (kbd "r") 'elfeed-search-untag-all-unread)
+  (define-key elfeed-search-mode-map (kbd "s") 'elfeed-search-live-filter))
 
 ;; Function to reload elfeed-org configuration
 (defun elfeed-org-reload ()