platform: modularize api/gui, add docs-tests-web foundation, and refresh root config

selective-vpn-api/app/watchers_runtime.go

@@ -0,0 +1,98 @@
+package app
+
+import (
+	"context"
+	"strings"
+	"time"
+)
+
+// ---------------------------------------------------------------------
+// autoloop watcher
+// ---------------------------------------------------------------------
+
+func watchAutoloop(ctx context.Context, every time.Duration) {
+	lastWord := ""
+	lastRaw := ""
+	for {
+		select {
+		case <-ctx.Done():
+			return
+		case <-time.After(every):
+		}
+
+		lines := tailFile(autoloopLogPath, 200)
+		word, raw := parseAutoloopStatus(lines)
+		if word == "" && raw == "" {
+			continue
+		}
+		if word == lastWord && raw == lastRaw {
+			continue
+		}
+		lastWord, lastRaw = word, raw
+		events.push("autoloop_status_changed", map[string]string{
+			"status_word": word,
+			"raw_text":    raw,
+		})
+	}
+}
+
+// ---------------------------------------------------------------------
+// systemd unit watcher
+// ---------------------------------------------------------------------
+
+func watchSystemdUnit(ctx context.Context, unit string, kind string, every time.Duration) {
+	last := ""
+	for {
+		select {
+		case <-ctx.Done():
+			return
+		case <-time.After(every):
+		}
+
+		stdout, _, _, err := runCommand("systemctl", "is-active", unit)
+		state := strings.TrimSpace(stdout)
+		if err != nil || state == "" {
+			state = "unknown"
+		}
+		if state == last {
+			continue
+		}
+		last = state
+		events.push("unit_state_changed", map[string]string{
+			"unit":  unit,
+			"kind":  kind,
+			"state": state,
+		})
+	}
+}
+
+func watchSystemdUnitDynamic(ctx context.Context, resolveUnit func() string, kind string, every time.Duration) {
+	lastUnit := ""
+	lastState := ""
+	for {
+		select {
+		case <-ctx.Done():
+			return
+		case <-time.After(every):
+		}
+
+		unit := strings.TrimSpace(resolveUnit())
+		state := "unknown"
+		if unit != "" {
+			stdout, _, _, err := runCommand("systemctl", "is-active", unit)
+			s := strings.TrimSpace(stdout)
+			if err == nil && s != "" {
+				state = s
+			}
+		}
+		if unit == lastUnit && state == lastState {
+			continue
+		}
+		lastUnit, lastState = unit, state
+		events.push("unit_state_changed", map[string]string{
+			"unit":  unit,
+			"kind":  kind,
+			"state": state,
+		})
+	}
+}