Improve startup performance and reduce resource usage

- Defer elfeed auto-update timers until first use (was running at startup)
- Fix consult-project-function to handle nil project gracefully
- Remove duplicate delete-trailing-whitespace hook
- Remove redundant diff-hl find-file-hook (global-diff-hl-mode handles it)
- Reduce treemacs resource usage (lower git entries, disable filewatch)
- Make dired dotfiles-first sorting opt-in (C-c s to sort, C-c S to toggle)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

lisp/elfeed-config.el

@@ -51,15 +51,16 @@
                     (lambda ()
                       (message "Feed update complete!"))))
   
-  ;; Store timer references so we can cancel them
+  ;; Timer references for auto-updates (started lazily on first elfeed use)
   (defvar elfeed-update-timer-30min nil
     "Timer for 30-minute elfeed updates.")
-  
-  ;; Auto-update feeds every 30 minutes in the background
-  ;; Delayed start to avoid impacting startup performance
-  (setq elfeed-update-timer-30min
-        (run-with-timer (* 5 60) (* 30 60) #'elfeed-update-async))
-  
+
+  (defvar elfeed-update-timer-hourly nil
+    "Timer for hourly elfeed updates.")
+
+  (defvar elfeed-timers-initialized nil
+    "Whether elfeed auto-update timers have been started.")
+
   ;; Custom function for fuzzy relative timestamps
   (defun my-elfeed-search-format-date (date)
     "Format DATE as a fuzzy relative time string."
@@ -181,6 +182,9 @@
 
 ;; Keybindings for elfeed
 (with-eval-after-load 'elfeed
+  ;; Start auto-update timers when elfeed is first opened (lazy initialization)
+  (add-hook 'elfeed-search-mode-hook #'elfeed-maybe-start-auto-updates)
+
   ;; Disable CUA mode in elfeed buffers to allow single-key commands
   (add-hook 'elfeed-search-mode-hook
             (lambda ()
@@ -213,14 +217,6 @@
     (rmh-elfeed-org-process rmh-elfeed-org-files rmh-elfeed-org-tree-id)
     (message "Elfeed feeds reloaded from org files. %d feeds loaded." (length elfeed-feeds))))
 
-;; Store timer reference for hourly updates
-(defvar elfeed-update-timer-hourly nil
-  "Timer for hourly elfeed updates.")
-
-;; Update feeds every hour
-(setq elfeed-update-timer-hourly
-      (run-at-time 0 (* 60 60) 'elfeed-update))
-
 ;; Functions to control auto-updates
 (defun elfeed-stop-auto-updates ()
   "Stop all automatic elfeed feed updates."
@@ -231,6 +227,7 @@
   (when (timerp elfeed-update-timer-hourly)
     (cancel-timer elfeed-update-timer-hourly)
     (setq elfeed-update-timer-hourly nil))
+  (setq elfeed-timers-initialized nil)
   (message "Elfeed auto-updates stopped."))
 
 (defun elfeed-start-auto-updates ()
@@ -240,9 +237,16 @@
   (setq elfeed-update-timer-30min
         (run-with-timer (* 5 60) (* 30 60) #'elfeed-update-async))
   (setq elfeed-update-timer-hourly
-        (run-at-time 0 (* 60 60) 'elfeed-update))
+        (run-at-time (* 5 60) (* 60 60) 'elfeed-update))
+  (setq elfeed-timers-initialized t)
   (message "Elfeed auto-updates started."))
 
+(defun elfeed-maybe-start-auto-updates ()
+  "Start auto-updates if not already initialized.
+This is called when elfeed is first opened."
+  (unless elfeed-timers-initialized
+    (elfeed-start-auto-updates)))
+
 ;; Sorting functions
 (defun elfeed-sort-by-date-ascending ()
   "Sort elfeed entries by date ascending (oldest first)."