feat: add Smart Fridge shell and per-credential shell routing

Implement Samsung FridgeOS-themed shell (PLAN.md §3.3) with inventory
management, temperature controls, diagnostics, alerts, and other
appliance commands. Add per-credential shell routing so static
credentials can specify which shell to use via the `shell` config field,
passed through ssh.Permissions.Extensions.

Also extract shared ReadLine helper from bash to the shell package so
both shells can reuse terminal input handling.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

internal/shell/fridge/fridge_test.go

@@ -0,0 +1,233 @@
+package fridge
+
+import (
+	"bytes"
+	"context"
+	"io"
+	"strings"
+	"testing"
+	"time"
+
+	"git.t-juice.club/torjus/oubliette/internal/shell"
+	"git.t-juice.club/torjus/oubliette/internal/storage"
+)
+
+type rwCloser struct {
+	io.Reader
+	io.Writer
+}
+
+func (r *rwCloser) Close() error { return nil }
+
+func runShell(t *testing.T, commands string) string {
+	t.Helper()
+	store := storage.NewMemoryStore()
+	sessID, _ := store.CreateSession(context.Background(), "127.0.0.1", "root", "fridge")
+
+	sess := &shell.SessionContext{
+		SessionID: sessID,
+		Username:  "root",
+		Store:     store,
+		CommonConfig: shell.ShellCommonConfig{
+			Hostname: "testhost",
+		},
+	}
+
+	rw := &rwCloser{
+		Reader: bytes.NewBufferString(commands),
+		Writer: &bytes.Buffer{},
+	}
+
+	sh := NewFridgeShell()
+	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+	defer cancel()
+
+	if err := sh.Handle(ctx, sess, rw); err != nil {
+		t.Fatalf("Handle: %v", err)
+	}
+
+	return rw.Writer.(*bytes.Buffer).String()
+}
+
+func TestFridgeShellName(t *testing.T) {
+	sh := NewFridgeShell()
+	if sh.Name() != "fridge" {
+		t.Errorf("Name() = %q, want %q", sh.Name(), "fridge")
+	}
+	if sh.Description() == "" {
+		t.Error("Description() should not be empty")
+	}
+}
+
+func TestBootBanner(t *testing.T) {
+	output := runShell(t, "exit\r")
+	if !strings.Contains(output, "FridgeOS-ARM") {
+		t.Error("output should contain FridgeOS-ARM in banner")
+	}
+	if !strings.Contains(output, "Samsung Smart Fridge OS") {
+		t.Error("output should contain Samsung Smart Fridge OS")
+	}
+	if !strings.Contains(output, "FridgeOS>") {
+		t.Error("output should contain FridgeOS> prompt")
+	}
+}
+
+func TestHelpCommand(t *testing.T) {
+	output := runShell(t, "help\rexit\r")
+	for _, keyword := range []string{"inventory", "temp", "status", "diagnostics", "alerts", "reboot", "exit"} {
+		if !strings.Contains(output, keyword) {
+			t.Errorf("help output should mention %q", keyword)
+		}
+	}
+}
+
+func TestInventoryList(t *testing.T) {
+	output := runShell(t, "inventory\rexit\r")
+	if !strings.Contains(output, "Fridge Inventory") {
+		t.Error("should show inventory header")
+	}
+	if !strings.Contains(output, "Whole Milk") {
+		t.Error("should list milk")
+	}
+	if !strings.Contains(output, "Eggs") {
+		t.Error("should list eggs")
+	}
+}
+
+func TestInventoryAdd(t *testing.T) {
+	output := runShell(t, "inventory add Cheese\rinventory\rexit\r")
+	if !strings.Contains(output, "Added 'Cheese'") {
+		t.Error("should confirm adding cheese")
+	}
+	if !strings.Contains(output, "Cheese") {
+		t.Error("inventory list should contain cheese")
+	}
+}
+
+func TestInventoryRemove(t *testing.T) {
+	output := runShell(t, "inventory remove milk\rinventory\rexit\r")
+	if !strings.Contains(output, "Removed") {
+		t.Error("should confirm removal")
+	}
+}
+
+func TestTemperature(t *testing.T) {
+	output := runShell(t, "temp\rexit\r")
+	if !strings.Contains(output, "37") {
+		t.Error("should show fridge temp 37°F")
+	}
+	if !strings.Contains(output, "Fridge") {
+		t.Error("should label fridge zone")
+	}
+	if !strings.Contains(output, "Freezer") {
+		t.Error("should label freezer zone")
+	}
+}
+
+func TestTempSetValid(t *testing.T) {
+	output := runShell(t, "temp set fridge 40\rtemp\rexit\r")
+	if !strings.Contains(output, "set to 40") {
+		t.Errorf("should confirm temp set, got: %s", output)
+	}
+	// Second temp call should show 40.
+	if !strings.Contains(output, "40") {
+		t.Error("temperature should now be 40")
+	}
+}
+
+func TestTempSetOutOfRange(t *testing.T) {
+	output := runShell(t, "temp set fridge 100\rexit\r")
+	if !strings.Contains(output, "WARNING") {
+		t.Error("should warn about out-of-range temp")
+	}
+}
+
+func TestTempSetFreezerOutOfRange(t *testing.T) {
+	output := runShell(t, "temp set freezer 50\rexit\r")
+	if !strings.Contains(output, "WARNING") {
+		t.Error("should warn about out-of-range freezer temp")
+	}
+}
+
+func TestStatus(t *testing.T) {
+	output := runShell(t, "status\rexit\r")
+	for _, keyword := range []string{"Compressor", "WiFi", "Ice maker", "TikTok", "Spotify", "SmartHome"} {
+		if !strings.Contains(output, keyword) {
+			t.Errorf("status should contain %q", keyword)
+		}
+	}
+}
+
+func TestDiagnostics(t *testing.T) {
+	output := runShell(t, "diagnostics\rexit\r")
+	if !strings.Contains(output, "ALL SYSTEMS NOMINAL") {
+		t.Error("diagnostics should end with ALL SYSTEMS NOMINAL")
+	}
+}
+
+func TestAlerts(t *testing.T) {
+	output := runShell(t, "alerts\rexit\r")
+	if !strings.Contains(output, "Active Alerts") {
+		t.Error("should show alerts header")
+	}
+	if !strings.Contains(output, "Firmware update") {
+		t.Error("should mention firmware update")
+	}
+}
+
+func TestReboot(t *testing.T) {
+	output := runShell(t, "reboot\r")
+	if !strings.Contains(output, "rebooting") || !strings.Contains(output, "Rebooting") {
+		t.Error("should show reboot message")
+	}
+}
+
+func TestUnknownCommand(t *testing.T) {
+	output := runShell(t, "foobar\rexit\r")
+	if !strings.Contains(output, "unknown command") {
+		t.Error("should show unknown command message")
+	}
+}
+
+func TestExitCommand(t *testing.T) {
+	output := runShell(t, "exit\r")
+	if !strings.Contains(output, "Goodbye") {
+		t.Error("exit should show goodbye message")
+	}
+}
+
+func TestLogoutCommand(t *testing.T) {
+	output := runShell(t, "logout\r")
+	if !strings.Contains(output, "Goodbye") {
+		t.Error("logout should show goodbye message")
+	}
+}
+
+func TestSessionLogs(t *testing.T) {
+	store := storage.NewMemoryStore()
+	sessID, _ := store.CreateSession(context.Background(), "127.0.0.1", "root", "fridge")
+
+	sess := &shell.SessionContext{
+		SessionID: sessID,
+		Username:  "root",
+		Store:     store,
+		CommonConfig: shell.ShellCommonConfig{
+			Hostname: "testhost",
+		},
+	}
+
+	rw := &rwCloser{
+		Reader: bytes.NewBufferString("help\rexit\r"),
+		Writer: &bytes.Buffer{},
+	}
+
+	sh := NewFridgeShell()
+	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+	defer cancel()
+
+	sh.Handle(ctx, sess, rw)
+
+	if len(store.SessionLogs) < 2 {
+		t.Errorf("expected at least 2 session logs, got %d", len(store.SessionLogs))
+	}
+}