feat: toml config support (#9)

## What's new
- TOML config support 
- add config init command to justfile
https://github.com/versenilvis/IRIS/pull/9/commits/a5bb6c23d74ca73385b3590d2eb275ce6429906b
- add copy binary file to local bin on reload
https://github.com/versenilvis/IRIS/pull/9/commits/4da3acdbc58c28f20fa0021d15fec82823ba392b
- init config on setup
https://github.com/versenilvis/IRIS/pull/9/commits/fb48b6bb832f38e24fab9211d92858bab9a58a07

## Fix
- add lsof to support macos because /proc filesystem is Linux-specific
and does not exist on macOS 0439d829573864fcf902fc4127f7d45384bfab01
- git push doesnt suggest current branch, fix
https://github.com/versenilvis/IRIS/pull/9/commits/b498532b401b764a4a1a2c70b3cb44b7caf72320
- use timeout context for lsof command in reload handler
https://github.com/versenilvis/IRIS/pull/9/commits/1a2baee951e6538a729da12aedfe53960e51102d

config/defaults.go

@@ -0,0 +1,38 @@
+package config
+
+import "time"
+
+func DefaultConfig() *Config {
+	return &Config{
+		Core: CoreConfig{
+			Version: 1,
+			Shell:   "",
+			Mode:    "last",
+			Debug:   false,
+		},
+		UI: UIConfig{
+			GhostText:      true,
+			MaxSuggestions: 100,
+			MaxHeight:      15,
+		},
+		Git: GitConfig{
+			FilterActiveBranch:  true,
+			DeduplicateBranches: true,
+		},
+		Updater: UpdaterConfig{
+			CheckOnStartup: true,
+			Channel:        "stable",
+			CheckInterval:  Duration(24 * time.Hour),
+		},
+	}
+}
+
+func DefaultState() *State {
+	return &State{
+		LastMode: "spec",
+		Updater: UpdaterState{
+			LastCheckTime: time.Time{},
+			SeenVersion:   "",
+		},
+	}
+}