feat: tab navigation in modal (Index/Transkript/Zusammenfassung)

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

output.py

@@ -36,10 +36,15 @@ def save_transcript(
 
 
 def read_transcript(output_dir: str, filename: str) -> str | None:
-    """Return file content if filename is a plain .md file inside output_dir."""
-    if os.path.basename(filename) != filename or not filename.endswith(".md"):
+    """Return file content for a .md file inside output_dir (flat or one level deep)."""
+    if not filename.endswith(".md"):
+        return None
+    parts = filename.split("/")
+    if len(parts) > 2 or any(p in (".", "..") or not p for p in parts):
         return None
     path = os.path.join(output_dir, filename)
+    if not os.path.abspath(path).startswith(os.path.abspath(output_dir) + os.sep):
+        return None
     if not os.path.exists(path):
         return None
     with open(path, encoding="utf-8") as f:
@@ -57,7 +62,17 @@ def list_transcripts(output_dir: str, limit: int = 20) -> list[dict]:
     for f in files:
         full = os.path.join(output_dir, f)
         stat = os.stat(full)
-        result.append({"filename": f, "path": full, "size": stat.st_size, "mtime": stat.st_mtime})
+        item: dict = {"filename": f, "path": full, "size": stat.st_size, "mtime": stat.st_mtime}
+        if f.endswith("-index.md"):
+            base = f[: -len("-index.md")]
+            related: dict[str, str] = {}
+            for suffix, key in [("-transkript.md", "transkript"), ("-zusammenfassung.md", "zusammenfassung")]:
+                rel_filename = f"{base}/{base}{suffix}"
+                if os.path.exists(os.path.join(output_dir, rel_filename)):
+                    related[key] = rel_filename
+            if related:
+                item["related"] = related
+        result.append(item)
     return result