feat(file-history): customize the max length of commit subject before truncating

Author: li6in9muyou

lua/diffview/scene/views/file_history/render.lua

@@ -142,7 +142,8 @@ local function render_entries(panel, parent, entries, updating)
       comp:add_text((" (%s)"):format(entry.commit.ref_names), "DiffviewReference")
     end
 
-    local subject = utils.str_trunc(entry.commit.subject, 72)
+    local subject =
+      utils.str_trunc(entry.commit.subject, c.file_history_panel.max_len_commit_subject or 72)
 
     if subject == "" then
       subject = "[empty message]"