docs: add community tools section

Reference BIOS Preservation Tool by monster-penguin in README,
wiki, and site nav.

wiki/community-tools.md

@@ -0,0 +1,21 @@
+# Community tools
+
+Projects built on RetroBIOS data.
+
+---
+
+## BIOS Preservation Tool
+
+**Author:** [monster-penguin](https://github.com/monster-penguin)
+**Repository:** [github.com/monster-penguin/BIOS-Preservation-Tool](https://github.com/monster-penguin/BIOS-Preservation-Tool)
+**License:** MIT
+
+A local tool for managing your own BIOS collection. Point it at your files, it verifies them against RetroBIOS platform YAMLs, stores them in a deduplicated database, and produces ready-to-use directories for each platform. Supports scanning directories, archives, and URLs.
+
+See the project's [README](https://github.com/monster-penguin/BIOS-Preservation-Tool#readme) for setup and usage.
+
+---
+
+!!! note "Add your project"
+
+    Open an issue with a link to your repository.

wiki/index.md

@@ -28,6 +28,10 @@ If you just want to download BIOS packs, see the [home page](../index.md).
 
 See [contributing](../contributing.md) for submission guidelines.
 
+## Community
+
+- **[Community tools](community-tools.md)** - projects built on RetroBIOS data
+
 ## Glossary
 
 - **BIOS** - firmware burned into console hardware, needed by emulators that rely on original boot code