refactor: __init__.py as single version source; pyproject.toml reads dynamically; paperforge.json drops version field

paperforge.json

@@ -1,6 +1,5 @@
 {
   "name": "PaperForge-Lite",
-  "version": "1.4.4",
   "description": "Lightweight literature management automation for Obsidian + Zotero",
   "repository": "https://github.com/LLLin000/PaperForge",
   "update": {

paperforge/worker/update.py

@@ -303,10 +303,10 @@ def run_update(vault: Path) -> int:
         from importlib.metadata import version as _pkg_ver
         local = _pkg_ver("paperforge")
     except Exception:
-        local_cfg = vault / "paperforge.json"
-        if local_cfg.exists():
-            local = json.loads(local_cfg.read_text(encoding="utf-8")).get("version", "unknown")
-        else:
+        try:
+            import paperforge
+            local = paperforge.__version__
+        except Exception:
             local = "unknown"
     remote = _remote_version()
     logger.info("%s", "=" * 50)

pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "setuptools.build_meta"
 
 [project]
 name = "paperforge"
-version = "1.4.4"
+dynamic = ["version"]
 description = "PaperForge — Obsidian + Zotero literature pipeline CLI"
 readme = "README.md"
 requires-python = ">=3.10"
@@ -46,6 +46,9 @@ paperforge = "paperforge.cli:main"
 where = ["."]
 include = ["paperforge*"]
 
+[tool.setuptools.dynamic]
+version = {attr = "paperforge.__version__"}
+
 [tool.setuptools.package-data]
 paperforge = [
     "py.typed",