fix: safely check mini.diff, check if tests pass

lua/codecompanion/strategies/inline/miniDiff.lua

@@ -5,15 +5,12 @@ local M = {}
 local original_buffer_content = {} -- Store the original buffer content
 local codecompanion_buffers = {} -- Store which buffers are using CodeCompanion source
 local revert_timers = {} -- Store timers for reverting to Git source
-local MiniDiff
-local ok, err = pcall(function()
-  MiniDiff = require("mini.diff")
-end)
+local log = require("codecompanion.utils.log")
+local ok, MiniDiff = pcall(require, "mini.diff")
 if not ok then
-  vim.notify("Failed to load mini.diff: " .. err, vim.log.levels.WARN)
+  return log:error("Failed to load mini.diff: ", vim.log.levels.WARN)
 end
 local git_source = MiniDiff.gen_source.git()
-local log = require("codecompanion.utils.log")
 
 ---@param buf_id number
 ---@return boolean Whether