feat(scan): binary FIX scan reads frl_/frd_ names from .aep (no AE, never hangs)

Root cause of 'stuck on AE': heavy expression-driven projects take >10min for AE
to open, exceeding the scan timeout → job dies → admin UI stuck 'scanning'.

Fix: extend the stdlib .aep RIFX parser to collect every Utf8 name (ParseNames),
since FIX media placeholders are renamed footage ITEMS (frl_c1m1), not layers, and
text are layer names (frl_c1t1) — both are Utf8 chunks. QuickScan now branches on
?mode= (or auto-detects frl_ names) and scaffolds FIX scenes/elements + frd_*color
slots directly from the binary. Verified on the real final.aep that timed out in AE:
1 scene, 6 elements, 4 colors in 0.5s vs 10-min AE timeout.

Admin 'Quick scan (no AE)' is now the recommended path and passes the project mode.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

services/render/internal/handlers/scan_fix_test.go

@@ -0,0 +1,37 @@
+package handlers
+
+import (
+	"encoding/json"
+	"os"
+	"testing"
+
+	"github.com/flatrender/render-svc/internal/aep"
+)
+
+// TestBuildFixResultRealAEP: set FR_TEST_AEP to a FIX .aep to see the scenes the
+// binary parser scaffolds (no AE). Skipped in normal runs.
+func TestBuildFixResultRealAEP(t *testing.T) {
+	path := os.Getenv("FR_TEST_AEP")
+	if path == "" {
+		t.Skip("set FR_TEST_AEP")
+	}
+	data, err := os.ReadFile(path)
+	if err != nil {
+		t.Fatal(err)
+	}
+	names, err := aep.ParseNames(data)
+	if err != nil {
+		t.Fatal(err)
+	}
+	res := buildFixResult(names)
+	b, _ := json.MarshalIndent(res, "", "  ")
+	t.Logf("FIX scan result:\n%s", string(b))
+	if len(res.Scenes) == 0 {
+		t.Fatalf("expected at least one scene")
+	}
+	total := 0
+	for _, s := range res.Scenes {
+		total += len(s.Elements)
+	}
+	t.Logf("scenes=%d  total elements=%d  shared_colors=%d", len(res.Scenes), total, len(res.SharedColors))
+}