feat: add channels directory with 44 channel adapter definitions (#21)
* feat: add channels directory with 44 channel adapter definitions
Add TOML definitions for all 44 channel adapters supported by LibreFang,
matching the adapters in librefang-channels crate source code.
Each channel file includes: id, name, description, category, icon,
protocol, and metadata (url, docs).
Categories: messaging, social, enterprise, developer, iot, email.
Also adds channels template at templates/channel.toml.
* fix: format templates/channel.toml with taplo
Evan
644213eef6