Prepare repo for GitHub publication

- Add MIT LICENSE file
- Expand .gitignore with standard Rust/Linux entries
- Remove dangling symlinks (breadmancli, breadpadcli) and dev scratchpad (svgs.txt) from git tracking
- Replace unsafe unwrap() calls with expect() in breadman CLI (guarded by prior filter)

breadman/Cargo.toml

@@ -20,3 +20,4 @@ tokio.workspace = true
 chrono.workspace = true
 gtk4.workspace = true
 dirs.workspace = true
+futures-channel = "0.3"