feat(backend): add kiro account support

backend/internal/pkg/kiro/oauth_test.go

@@ -0,0 +1,56 @@
+//go:build unit
+
+package kiro
+
+import (
+	"fmt"
+	"testing"
+	"time"
+)
+
+func TestBuildSocialSignInURLUsesAppPortal(t *testing.T) {
+	got := BuildSocialSignInURL("http://localhost:49153", "challenge123", "state456")
+	want := "https://app.kiro.dev/signin?code_challenge=challenge123&code_challenge_method=S256&redirect_from=KiroIDE&redirect_uri=http%3A%2F%2Flocalhost%3A49153&state=state456"
+	if got != want {
+		t.Fatalf("BuildSocialSignInURL() = %q, want %q", got, want)
+	}
+}
+
+func TestBuildSocialTokenRedirectURI(t *testing.T) {
+	got := BuildSocialTokenRedirectURI("http://localhost:49153", "/oauth/callback", "github")
+	want := "http://localhost:49153/oauth/callback?login_option=github"
+	if got != want {
+		t.Fatalf("BuildSocialTokenRedirectURI() = %q, want %q", got, want)
+	}
+}
+
+func TestSessionStoreGetDeletesExpiredSession(t *testing.T) {
+	store := NewSessionStore()
+	store.Set("expired", &AuthSession{CreatedAt: time.Now().Add(-2 * sessionTTL)})
+
+	session, ok := store.Get("expired")
+	if ok || session != nil {
+		t.Fatalf("Get(expired) = (%v, %v), want (nil, false)", session, ok)
+	}
+	if _, exists := store.data["expired"]; exists {
+		t.Fatalf("expired session should be deleted from the store")
+	}
+}
+
+func TestSessionStoreSetPrunesExpiredSessions(t *testing.T) {
+	store := NewSessionStore()
+	now := time.Now()
+	for i := 0; i < sessionCleanupMin; i++ {
+		store.data[fmt.Sprintf("expired-%d", i)] = &AuthSession{CreatedAt: now.Add(-2 * sessionTTL)}
+	}
+	store.setCount = sessionCleanupEvery - 1
+
+	store.Set("fresh", &AuthSession{CreatedAt: now})
+
+	if len(store.data) != 1 {
+		t.Fatalf("store size = %d, want 1", len(store.data))
+	}
+	if _, ok := store.data["fresh"]; !ok {
+		t.Fatalf("fresh session should remain after pruning")
+	}
+}