perf(git/repo): cache ref/file lookups, invalidate on status refresh

lua/git/cmd.lua

@@ -317,22 +317,26 @@ end
 ---@param dir string
 ---@return string[]
 local function list_files(r, dir)
-    local cmd = { "git", "ls-files" }
-    if dir ~= "" then
-        table.insert(cmd, dir)
-    end
-    local out = util.exec(cmd, { cwd = r.worktree, silent = true })
-    return out and util.split_lines(out) or {}
+    return r:get_cached("files:" .. dir, function(self)
+        local cmd = { "git", "ls-files" }
+        if dir ~= "" then
+            table.insert(cmd, dir)
+        end
+        local out = util.exec(cmd, { cwd = self.worktree, silent = true })
+        return out and util.split_lines(out) or {}
+    end)
 end
 
 ---@param r ow.Git.Repo
 ---@return string[]
 local function list_remotes(r)
-    local out = util.exec(
-        { "git", "remote" },
-        { cwd = r.worktree, silent = true }
-    )
-    return out and util.split_lines(out) or {}
+    return r:get_cached("remotes", function(self)
+        local out = util.exec(
+            { "git", "remote" },
+            { cwd = self.worktree, silent = true }
+        )
+        return out and util.split_lines(out) or {}
+    end)
 end
 
 ---@type table<string, string[]>
@@ -469,7 +473,8 @@ function M.complete_rev(arg_lead)
 
     local colon = arg_lead:find(":", 1, true)
     if not colon then
-        local refs = r:list_refs()
+        local refs = {}
+        vim.list_extend(refs, r:list_refs())
         vim.list_extend(refs, r:list_pseudo_refs())
         vim.list_extend(refs, r:list_stash_refs())
         return prefix_filter(refs, arg_lead)