Use Magit's refresh cache for the duration of a menu refresh

We could additionally call `forge-current-{topic,issue,pullreq}' up
front and `cl-letf' functions that return these predetermined values,
but that is riskier and would preform unnecessary work for menus whose
suffixes don't actually call any of these functions, so we'll leave that
for another day.

Closes #712.

lisp/forge-commands.el

@@ -57,6 +57,7 @@ Takes the pull-request as only argument and must return a directory."
   "Dispatch a forge command."
   :transient-non-suffix #'transient--do-call
   :refresh-suffixes t
+  :environment #'forge--menu-environment
   :column-widths forge--topic-menus-column-widths
   [forge--topic-menus-group
    ["Fetch"
@@ -116,6 +117,7 @@ Takes the pull-request as only argument and must return a directory."
   "Configure current repository and global settings."
   :transient-non-suffix #'transient--do-call
   :refresh-suffixes t
+  :environment #'forge--menu-environment
   :column-widths forge--topic-menus-column-widths
   [forge--topic-menus-group
    ["Configure"

lisp/forge-notify.el

@@ -154,6 +154,7 @@ signal an error."
   :transient-non-suffix #'transient--do-call
   :transient-switch-frame nil
   :refresh-suffixes t
+  :environment #'forge--menu-environment
   :column-widths forge--topic-menus-column-widths
   [:hide always ("q" forge-menu-quit-list)]
   [forge--topic-menus-group

lisp/forge-repos.el

@@ -130,6 +130,7 @@ Must be set before `forge-list' is loaded.")
   :transient-non-suffix #'transient--do-call
   :transient-switch-frame nil
   :refresh-suffixes t
+  :environment #'forge--menu-environment
   :column-widths forge--topic-menus-column-widths
   [:hide always ("q" forge-menu-quit-list)]
   [forge--topic-menus-group

lisp/forge-topic.el

@@ -1312,6 +1312,7 @@ This mode itself is never used directly."
   :transient-non-suffix #'transient--do-call
   :transient-switch-frame nil
   :refresh-suffixes t
+  :environment #'forge--menu-environment
   :column-widths forge--topic-menus-column-widths
   [:hide always ("q" forge-menu-quit-list)]
   [forge--topic-menus-group
@@ -1348,13 +1349,19 @@ This mode itself is never used directly."
 ;;;###autoload(autoload 'forge-topic-state-menu "forge-topic" nil t)
 (transient-define-prefix forge-topic-state-menu ()
   "Set state of the current topic."
+  :environment #'forge--menu-environment
   [forge--topic-set-state-group])
 
 ;;;###autoload(autoload 'forge-topic-status-menu "forge-topic" nil t)
 (transient-define-prefix forge-topic-status-menu ()
   "Set status of the current topic."
+  :environment #'forge--menu-environment
   [forge--topic-set-status-group])
 
+(defun forge--menu-environment (fn)
+  (let ((magit--refresh-cache (list (cons 0 0))))
+    (funcall fn)))
+
 ;;;; State
 
 (defclass forge--topic-set-state-command (transient-suffix)

lisp/forge-topics.el

@@ -185,6 +185,7 @@ Must be set before `forge-topics' is loaded.")
   :transient-non-suffix #'transient--do-call
   :transient-switch-frame nil
   :refresh-suffixes t
+  :environment #'forge--menu-environment
   :column-widths forge--topic-menus-column-widths
   [:hide always ("q" forge-menu-quit-list)]
   [forge--topic-menus-group