Migrate min_const_generics_plan from hack.md

Author: popzxc

README.md

@@ -59,6 +59,10 @@ yourself over there and ask us any questions you have.
 This repository is also an mdbook project. You can view and build it using the
 following command.
 
+> [!NOTE]  
+> Only `mdbook` v0.4 is currently supported. If you're using v0.5, install v0.4,
+> for example, via `cargo install mdbook --version ^0.4 --force`.
+
 ```
 mdbook-skill-tree install && mdbook serve
 ```

SUMMARY.md

@@ -18,4 +18,5 @@
     - [❓How to vision doc](./vision/how_to_vision_doc.md) 
 - [🔍 Meetings](./meetings/README.md)
 - [✏️ Draft RFCs](./draft-rfcs/README.md)
-s
+- [📁 Documents](./documents/README.md)
+    - [📝 The plan for `min_generic_const_args`](./documents/min_const_generics_plan.md)

documents/README.md

@@ -0,0 +1,14 @@
+# 📁 Documents
+
+This folder might contain various documents that are not RFCs or vision,
+but still are relevant for the project and worth keeping.
+
+<!-- Note for maintainers: 
+
+These documents might be linked from external repositories, primarily
+`rust-lang/rust`, so the layout is expected to be stable.
+
+If you're removing documents from here, do a best effort scan across 
+rust repo to make sure that it isn't linked anywhere.
+
+-->