feat(devcontainer): add development environment configuration

- Introduces a devcontainer.json for Xilinx ISE development setup
- Replaces project.cfg with project.yml for improved build clarity
- Updates .gitignore to exclude build artifacts and configuration files
- Removes outdated Git submodules and legacy project files
- Enhances VS Code settings for better UI customization
- Configures GPG signing and Python package installation post startup

.vscode/settings.json

@@ -0,0 +1,12 @@
+{
+    "workbench.colorCustomizations": {
+        "activityBar.activeBackground": "#d48282",
+        "activityBar.background": "#d48282",
+        "activityBar.foreground": "#15202b",
+        "activityBar.inactiveForeground": "#15202b99",
+        "activityBarBadge.background": "#b8e7b8",
+        "activityBarBadge.foreground": "#15202b"
+    },
+    "peacock.color": "#80d5e0",
+    "peacock.remoteColor": "#c75c5c"
+}