docs: make sure that plenary will be archived in Q2 2026

Author: Conni2461

README.md

@@ -1,5 +1,17 @@
 # plenary.nvim
 
+---
+
+## Important Notice
+
+This repository is no longer actively maintained and will be officially archived soon.
+
+* Critical bugs may still be addressed until **2026-06-30**
+* No new features will be added
+* Ongoing support should not be expected
+
+---
+
 All the lua functions I don't want to write twice.
 
 > plenary:
@@ -8,7 +20,7 @@ All the lua functions I don't want to write twice.
 
 Note that this library is useless outside of Neovim since it requires Neovim functions. It should be usable with any recent version of Neovim though.
 
-At the moment, it is very much in pre-alpha :smile: Expect changes to the way some functions are structured. I'm hoping to finish some document generators to provide better documentation for people to use and consume and then at some point we'll stabilize on a few more stable APIs.
+~~At the moment, it is very much in pre-alpha :smile: Expect changes to the way some functions are structured. I'm hoping to finish some document generators to provide better documentation for people to use and consume and then at some point we'll stabilize on a few more stable APIs.~~
 
 ## Installation