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, 9 insertions, 4 deletions

diff --git a/modules/modeline-config.el b/modules/modeline-config.el
index 771d960f..61ab0f9d 100644
--- a/modules/modeline-config.el
+++ b/modules/modeline-config.el
@@ -141,15 +141,20 @@ Uses built-in cached values for performance.")
 
 (defun cj/modeline-vc-fetch (file)
   "Fetch modeline VC data for FILE.
-Return a plist with `:branch' and `:state', or nil when FILE has no VC data."
+Return a plist with `:branch' and `:state', or nil when FILE has no VC data.
+Uses `vc-git--symbolic-ref' for branch names when available (it returns the
+symbolic ref like \"main\" instead of a SHA when HEAD is on a branch), but
+falls back to `vc-working-revision' if the internal accessor is missing --
+the symbol is internal and can be renamed or removed between Emacs versions."
   (unless (and (file-remote-p file) (not cj/modeline-vc-show-remote))
     (when-let* ((backend (vc-backend file))
                 (branch (vc-working-revision file backend)))
       (when (eq backend 'Git)
         (unless (fboundp 'vc-git--symbolic-ref)
-          (require 'vc-git))
-        (when-let* ((symbolic (vc-git--symbolic-ref file)))
-          (setq branch symbolic)))
+          (require 'vc-git nil 'noerror))
+        (when (fboundp 'vc-git--symbolic-ref)
+          (when-let* ((symbolic (ignore-errors (vc-git--symbolic-ref file))))
+            (setq branch symbolic))))
       (list :branch branch
             :state (vc-state file backend)))))