simplify the driver interface

app/mem/drivers/meminfo.go

@@ -2,6 +2,7 @@ package drivers
 
 import (
 	"bufio"
+	"fmt"
 	"os"
 	"strconv"
 	"strings"
@@ -9,12 +10,30 @@ import (
 
 type MemInfoDriver struct{}
 
-func NewMemInfoDriver() *MemInfoDriver {
-	return &MemInfoDriver{}
+func NewMemInfoDriver() (*MemInfoDriver, error) {
+	r := MemInfoDriver{}
+	_, err := r.Read()
+	return &r, err
+}
+
+func (r *MemInfoDriver) Render(console *strings.Builder) error {
+	u, err := r.Read()
+	if err != nil {
+		return err
+	}
+
+	usage := u.(MemoryUsage)
+
+	fmt.Fprintf(console, "--- Usage ---\n")
+	fmt.Fprintf(console, "%-16s | %.2f GiB\033[K\n", "Total", usage.TotalGB)
+	fmt.Fprintf(console, "%-16s | %.2f GiB (%.2f%%) \033[K\n", "Used", usage.UsedGB, usage.UsedPercent)
+	fmt.Fprintf(console, "%-16s | %.2f GiB\033[K\n", "Avail", usage.AvailableGB)
+
+	return nil
 }
 
 // Read /proc/meminfo for active system memory statistics
-func (r *MemInfoDriver) ReadUsageSensors() (MemoryUsage, error) {
+func (r *MemInfoDriver) Read() (any, error) {
 	usage := MemoryUsage{}
 	file, err := os.Open("/proc/meminfo")
 	if err != nil {