ax(mining): replace restatement comments on settings structs with usage examples

AX Principle 2 — comments must show HOW with real values, not restate WHAT
the type already says. WindowState, MinerDefaults and AppSettings all had
prose descriptions ("stores…") replaced with concrete call-site examples.

Co-Authored-By: Charon <charon@lethean.io>

pkg/mining/settings_manager.go

@@ -12,7 +12,8 @@ import (
 
 const settingsFileName = "settings.json"
 
-// WindowState stores the last window position and size
+// state := settingsManager.GetWindowState()
+// if state.Maximized { w.SetSize(state.Width, state.Height) }
 type WindowState struct {
 	X         int  `json:"x"`
 	Y         int  `json:"y"`
@@ -21,7 +22,7 @@ type WindowState struct {
 	Maximized bool `json:"maximized"`
 }
 
-// MinerDefaults stores default configuration for miners
+// settingsManager.SetMinerDefaults(MinerDefaults{DefaultPool: "pool.minexmr.com:4444", CPUMaxThreadsHint: 50})
 type MinerDefaults struct {
 	DefaultPool          string `json:"defaultPool,omitempty"`
 	DefaultWallet        string `json:"defaultWallet,omitempty"`
@@ -30,7 +31,8 @@ type MinerDefaults struct {
 	CPUThrottleThreshold int    `json:"cpuThrottleThreshold,omitempty"` // Throttle when CPU exceeds this %
 }
 
-// AppSettings stores application-wide settings
+// settings := settingsManager.Get()
+// if settings.Theme == "dark" { applyDarkMode() }
 type AppSettings struct {
 	// Window settings
 	Window WindowState `json:"window"`