chore: update Gradio to 6.12.0 and fix HF Spaces compatibility

- Update Gradio from 5.12.0 to 6.12.0
- Fix Gradio 6.x API changes (theme/css parameters moved to launch)
- Remove deprecated show_api parameter
- Fix circular import in root app.py using importlib
- Update HF Spaces SDK version in README
- Remove audioop-lts (not needed for Python 3.11)

README.md

@@ -4,7 +4,7 @@ emoji: 📄
 colorFrom: green
 colorTo: purple
 sdk: gradio
-sdk_version: 5.12.0
+sdk_version: 6.12.0
 app_file: app.py
 pinned: false
 license: apache-2.0

app.py

@@ -7,19 +7,44 @@ root stays uncluttered.
 
 from __future__ import annotations
 
+import importlib.util
 import sys
 from pathlib import Path
 
-_DEMO_DIR = Path(__file__).resolve().parent / "demo"
-sys.path.insert(0, str(_DEMO_DIR))
+_REPO_ROOT = Path(__file__).resolve().parent
 
-from app import demo  # noqa: E402,F401 — re-exported for HF Spaces
+# Add packages to path (needed before importing demo modules)
+for pkg in ("pdfsys-core", "pdfsys-router", "pdfsys-parser-mupdf", "pdfsys-bench"):
+    src = _REPO_ROOT / "packages" / pkg / "src"
+    if src.is_dir() and str(src) not in sys.path:
+        sys.path.insert(0, str(src))
+
+# Add demo dir to path (needed for pipeline import)
+_DEMO_DIR = _REPO_ROOT / "demo"
+if str(_DEMO_DIR) not in sys.path:
+    sys.path.insert(0, str(_DEMO_DIR))
+
+# Load demo app from demo/app.py using importlib to avoid name collision
+_demo_module_path = _DEMO_DIR / "app.py"
+spec = importlib.util.spec_from_file_location("demo_app", _demo_module_path)
+_demo_module = importlib.util.module_from_spec(spec)
+sys.modules["demo_app"] = _demo_module
+spec.loader.exec_module(_demo_module)
+demo = _demo_module.demo  # noqa: F401 — re-exported for HF Spaces
 
 if __name__ == "__main__":
     import os
 
+    import gradio as gr
+
+    CSS = """
+.small-num input { font-weight: 600; font-size: 1.1rem; }
+footer { display: none !important; }
+"""
+
     demo.queue(max_size=8).launch(
         server_name=os.environ.get("GRADIO_SERVER_NAME", "0.0.0.0"),
         server_port=int(os.environ.get("GRADIO_SERVER_PORT", "7860")),
-        show_api=False,
+        theme=gr.themes.Soft(primary_hue="emerald"),
+        css=CSS,
     )

demo/README.md

@@ -51,7 +51,7 @@ The root `README.md` already contains the required [Spaces YAML config](https://
 ---
 title: PDFSystem MNBVC Demo
 sdk: gradio
-sdk_version: 4.44.0
+sdk_version: 6.12.0
 app_file: app.py
 license: apache-2.0
 ---

demo/app.py

@@ -128,7 +128,7 @@ def process_pdf(
             "_No markdown yet._",
             empty_segments,
             empty_features,
-            {},
+            "{}",
         )
 
     pdf_path = Path(pdf_file)
@@ -154,7 +154,7 @@ def process_pdf(
             f"```\n{tb}\n```",
             empty_segments,
             empty_features,
-            err_json,
+            json.dumps(err_json, indent=2, ensure_ascii=False),
         )
 
     # ------------------------------------------------------------- summary
@@ -225,6 +225,7 @@ def process_pdf(
     raw = result.to_record()
     raw["router_features_full"] = result.router_features
     raw["segments_full"] = result.segments
+    raw_json_str = json.dumps(raw, indent=2, ensure_ascii=False, default=str)
 
     return (
         summary_md,
@@ -237,7 +238,7 @@ def process_pdf(
         md_text,
         seg_rows,
         feat_rows,
-        raw,
+        raw_json_str,
     )
 
 
@@ -279,7 +280,6 @@ def build_demo() -> gr.Blocks:
             with gr.Column(scale=2, min_width=520):
                 summary_md = gr.Markdown(
                     "Upload a PDF and click **Run Pipeline**.",
-                    label="Summary",
                 )
 
                 with gr.Row():
@@ -327,7 +327,7 @@ def build_demo() -> gr.Blocks:
                             label="Curated subset (full 124-dim vector in Raw JSON)",
                         )
                     with gr.Tab("Raw JSON"):
-                        raw_json = gr.JSON(label="All pipeline outputs")
+                        raw_json = gr.Code(label="All pipeline outputs", language="json")
 
         # ----------------------------------------------------------- wiring
         outputs = [

requirements.txt

@@ -2,15 +2,12 @@
 # Note: Local workspace packages (pdfsys-*) are loaded via sys.path in demo/app.py
 # and do not need editable installation in HF Spaces.
 
-# --- Python 3.13 compatibility (audioop removed) --------------------------
-audioop-lts
-
 # --- CPU-only torch (HF Spaces free tier is CPU) --------------------------
 --extra-index-url https://download.pytorch.org/whl/cpu
 torch>=2.1,<3.0
 
 # --- Third-party runtime deps -------------------------------------------
-gradio==5.12.0
+gradio>=5.12.0,<7.0
 huggingface-hub>=0.26,<0.29
 pymupdf>=1.24
 xgboost>=2.0