fix image has a terrible filename error, add neptunium tab

.gitignore

@@ -1,3 +1,5 @@
+*._md
+
 *.ipynb
 *.ignore
 1011_potential.html

_posts/2024-02-15-Altium-to-3d-GLTF.md

@@ -8,7 +8,7 @@ tags: [electronics, solidworks] # systems | embedded | rf | microwave | electron
 
 As part of the Neptunium flight computer, I wanted to create a proper webpage to showcase the flight computer. This will also be a landing page for people who want to use the wasm powered Neptunium Explorer, which will allow users to analyze flight data in the browser. At the center of this webpage I want to show an interactive 3d model of the flight computer
 
-![Neptunium website](/assets/img/2024-02-15-Altium-to-3d-GLTF/Screen%20Shot%202024-02-15%20at%2016.59.07.png){: height="500" }
+![Neptunium website](/assets/img/2024-02-15-Altium-to-3d-GLTF/website.png){: height="500" }
 
 While [Altium viewer](https://www.altium.com/viewer/) offers a method of showing PCBs in the browser as interactive 3d models, I wanted more control over this so I wanted to use the [`three.js`](https://threejs.org/) library to display the PCB.
 

_tabs/neptunium.md

@@ -0,0 +1,5 @@
+---
+icon: fas fa-microchip
+permalink: /neptunium/
+order: 5
+---

_tabs/old-site.md

@@ -1,7 +1,6 @@
 ---
 # the default layout is 'page'
 icon: fas fa-info-circle
-order: 5
+permalink: /legacy_site/index.html
+order: 6
 ---
-
-Legacy homepage: [https://peter-tanner.github.io/legacy_site/index.html](https://peter-tanner.github.io/legacy_site/index.html)