[review] create +lsp.el and +eglot.el files

This means we can remove a lot of `:unless (featurep! +eglot)`

modules/tools/lsp/+eglot.el

@@ -0,0 +1,23 @@
+;;; tools/lsp/+eglot.el -*- lexical-binding: t; -*-
+
+(use-package! eglot
+  :commands (eglot-ensure eglot)
+  :when (featurep! +eglot)
+  :init
+  (setq eglot-sync-connect 1
+        eglot-connect-timeout 10
+        eglot-autoshutdown t
+        eglot-send-changes-idle-time 0.5
+        ;; NOTE: Do NOT set eglot-auto-display-help-buffer to t.
+        ;; With popup-rule! :select t, eglot will steal focus from the source code very often.
+        eglot-auto-display-help-buffer nil)
+  :config
+  (set-popup-rule! "^\\*eglot-help" :size 0.35 :quit t :select t)
+  (when (featurep! :checkers syntax)
+    ;; Eager loading which is okay-ish since we want eglot to feed flycheck as soon as possible.
+    (load! "flycheck-eglot.el")
+    (require 'flycheck-eglot))
+  (set-lookup-handlers! 'eglot--managed-mode
+    :documentation #'+eglot/documentation-lookup-handler
+    :definition '(xref-find-definitions :async t)
+    :references '(xref-find-references :async t)))