Add Flatpak packaging for iDRAC6 console

- Manifest, desktop entry, metainfo, icon
- Direct Java launch (no javaws/IcedTea-Web)
- Bundles avctKVM.jar and native .so libs
- Parses JNLP for connection parameters
- sign-idrac.sh helper script

icons/scalable/com.idrac6.console.svg

@@ -0,0 +1,4 @@
+<svg xmlns='http://www.w3.org/2000/svg' width='128' height='128' viewBox='0 0 128 128'>
+<rect width='128' height='128' rx='16' fill='#0076ce'/>
+<text x='64' y='80' text-anchor='middle' font-family='sans-serif' font-size='48' font-weight='bold' fill='white'>i6</text>
+</svg>