feat: minimal diff (#583)

* Add minimize_diff option and add dummy function

* fix: minimize snippets

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Co-authored-by: yetone <yetoneful@gmail.com>

README.md

@@ -231,6 +231,7 @@ _See [config.lua#L9](./lua/avante/config.lua) for the full config_
     auto_set_keymaps = true,
     auto_apply_diff_after_generation = false,
     support_paste_from_clipboard = false,
+    minimize_diff = true, -- Whether to remove unchanged lines when applying a code block
   },
   mappings = {
     --- @class AvanteConflictMappings