Rewrite Strix from scratch as single binary

Complete architecture rewrite following go2rtc patterns:
- pkg/ for pure logic (camdb, tester, probe, generate)
- internal/ for application glue with Init() modules
- Single HTTP server on :4567 with all endpoints
- zerolog with password masking and memory ring buffer
- Environment-based config only (no YAML files)

API endpoints: /api/search, /api/streams, /api/test,
/api/probe, /api/generate, /api/health, /api/log

Dependencies: go2rtc v1.9.14, go-sqlite3, miekg/dns, zerolog

internal/app/app.go

@@ -0,0 +1,38 @@
+package app
+
+import (
+	"os"
+	"runtime"
+	"time"
+
+	"github.com/rs/zerolog"
+)
+
+var Version string
+
+var Logger zerolog.Logger
+
+var Info = map[string]any{}
+
+var StartTime = time.Now()
+
+// DB is the shared SQLite database path
+var DB string
+
+func Init() {
+	initLogger()
+
+	Info["version"] = Version
+	Info["platform"] = runtime.GOARCH
+
+	Logger.Info().Str("version", Version).Str("platform", runtime.GOARCH).Msg("[app] start")
+
+	DB = Env("STRIX_DB_PATH", "cameras.db")
+}
+
+func Env(key, def string) string {
+	if v := os.Getenv(key); v != "" {
+		return v
+	}
+	return def
+}