feat: modify the existing default devshell to use edaShell

[machshev]

Experimental new EDA devshell.

• Migrate the default devshell over to lowrisc-nix.lib.mkEdaShell to add support for commercial EDA tools versions are pulled from tool_data.json
• Removed unnecessary v prefix from Vivado version
• Removed the .envrc (direnv) config which does use flake - unfortunately the new EdaShell uses FHS bubblewrap to support the EDA tools on NixOS, it is not source-able. Which means it doesn't work with direnv. This will mean we will have to manually nix develop .

[marnovandermaas]

It looks like the bubble wrap is causing an error. Any idea how to fix this:

bwrap: No permissions to create a new namespace, likely because the kernel does not allow non-privileged user namespaces. On e.g. debian this can be enabled with 'sysctl kernel.unprivileged_userns_clone=1'.
Error: Process completed with exit code 1.