docs(readme): replace lazy.nvim FAQ with recipes reference

Problem: the FAQ inlined a lazy.nvim snippet that duplicates vimdoc
content and doesn't cover other plugin integrations.

Solution: replace with a generic "How do I integrate with plugin <X>?"
entry pointing to :help nonicons-recipes. Also track flake.lock.

README.md

@@ -32,14 +32,9 @@ luarocks install nonicons.nvim
 
 ## FAQ
 
-**How do I install with lazy.nvim?**
+**How do I integrate with plugin \<X\>?**
 
-```lua
-{
-  'barrettruth/nonicons.nvim',
-  dependencies = { 'nvim-tree/nvim-web-devicons' },
-}
-```
+See `:help nonicons-recipes`.
 
 ## Acknowledgements