TPA-RFC-77-B: Tails codebase cleanup, normalization and isolation

Full plan: TPA-RFC-77

Implement in the Tails Puppet code base:

• Remove the ENC
• Move node definitions under manifests/nodes.pp to roles, and prefix role names with tails_
• Switch to the directory structure used by Tor
• Move default configuration to a new profile::tails class and include it in all nodes
• Rename all profiles from tails::profile to profile::tails
• Ensure all exported resources' tags are prefixed with tails_
• Fix legacy facts → #42153