refactor(ui): four UI/navigation hygiene fixes from module-by-module re-review

- popper-config.el: move `(popper-mode +1)` and `(popper-echo-mode
  +1)` from the use-package `:init` block into `:config`.
  `:disabled t' on use-package skips `:config' but still runs
  `:init', so the previous shape enabled popper-mode on every load,
  including batch / test runs, despite the disabled marker.

- modeline-config.el: make `cj/modeline-vc-fetch' fall back when
  the internal `vc-git--symbolic-ref' is missing.  `require' uses
  `nil 'noerror', the call sits inside an `fboundp' guard, and
  `ignore-errors' wraps the call itself so an Emacs version that
  renames or removes the accessor leaves `branch' at
  `vc-working-revision''s output instead of crashing the modeline.

- ui-config.el: guard the cursor-color `post-command-hook' behind
  `(display-graphic-p)' both at install time and inside the
  function body.  Batch / TTY runs short-circuit cleanly with no
  per-command overhead.  A `server-after-make-frame-hook' catches
  the daemon case where the first GUI frame is created after
  ui-config loads and installs the hook lazily.  Updates
  test-ui-config--buffer-cursor-state and
  test-ui-cursor-color-integration to stub `display-graphic-p' so
  the work body still runs under batch.

- nerd-icons-config.el: drop `:demand t' (`:defer t' now), keeping
  the `:config' advice install as the natural lazy-on-load path.
  Add a `with-eval-after-load 'nerd-icons' block as a safety net for
  the already-loaded case on re-eval; the block uses `advice-member-p'
  so the advice never stacks.

1 files changed, 28 insertions, 13 deletions

diff --git a/modules/ui-config.el b/modules/ui-config.el
index 5d3a6643..39b86182 100644
--- a/modules/ui-config.el
+++ b/modules/ui-config.el
@@ -120,21 +120,36 @@ through to `read-only' and keeps the orange cursor."
 
 (defun cj/set-cursor-color-according-to-mode ()
   "Change cursor color according to buffer state (modified, read-only, overwrite).
-Only updates for real user buffers, not internal/temporary buffers."
-  ;; Only update cursor for real buffers (not internal ones like *temp*, *Echo Area*, etc.)
-  (unless (string-prefix-p " " (buffer-name))  ; Internal buffers start with space
-	(let ((color (alist-get (cj/--buffer-cursor-state) cj/buffer-status-colors)))
-	  ;; Only skip if BOTH color AND buffer are the same (optimization)
-	  ;; This allows color to update when buffer state changes
-	  (unless (and (string= color cj/-cursor-last-color)
-				   (string= (buffer-name) cj/-cursor-last-buffer))
-		(set-cursor-color color)
-		(setq cj/-cursor-last-color color
-			  cj/-cursor-last-buffer (buffer-name))))))
+Only updates for real user buffers, not internal/temporary buffers.
+A no-op on non-graphical frames -- TTY/batch sessions have no cursor color
+to set."
+  (when (display-graphic-p)
+    ;; Only update cursor for real buffers (not internal ones like *temp*, *Echo Area*, etc.)
+    (unless (string-prefix-p " " (buffer-name))  ; Internal buffers start with space
+      (let ((color (alist-get (cj/--buffer-cursor-state) cj/buffer-status-colors)))
+        ;; Only skip if BOTH color AND buffer are the same (optimization)
+        ;; This allows color to update when buffer state changes
+        (unless (and (string= color cj/-cursor-last-color)
+                     (string= (buffer-name) cj/-cursor-last-buffer))
+          (set-cursor-color color)
+          (setq cj/-cursor-last-color color
+                cj/-cursor-last-buffer (buffer-name)))))))
 
 ;; Use post-command-hook to update cursor color after every command
-;; This ensures cursor color always matches the current buffer's state
-(add-hook 'post-command-hook #'cj/set-cursor-color-according-to-mode)
+;; This ensures cursor color always matches the current buffer's state.
+;; The hook only registers under a graphical session so batch / TTY runs
+;; don't pay per-command overhead for a no-op.
+(when (display-graphic-p)
+  (add-hook 'post-command-hook #'cj/set-cursor-color-according-to-mode))
+;; Daemon mode: the first frame may be created after this module loads.
+;; Re-attempt the hook install once a GUI frame appears.
+(add-hook 'server-after-make-frame-hook
+          (lambda ()
+            (when (and (display-graphic-p)
+                       (not (memq #'cj/set-cursor-color-according-to-mode
+                                  post-command-hook)))
+              (add-hook 'post-command-hook
+                        #'cj/set-cursor-color-according-to-mode))))
 
 ;; Don’t show a cursor in non-selected windows:
 (setq cursor-in-non-selected-windows nil)