Improve PyPI proxy and Package page UX

PyPI proxy improvements:
- Set package format to "pypi" instead of "generic"
- Extract version from filename and create PackageVersion record
- Support .whl, .tar.gz, and .zip filename formats

Package page UX overhaul:
- Move upload to header button with modal
- Simplify table: combine Tag/Version, remove Type and Artifact ID columns
- Add row action menu (⋯) with: Copy ID, Ensure File, Create Tag, Dependencies
- Remove cluttered "Download by Artifact ID" and "Create/Update Tag" sections
- Add modals for upload and create tag actions
- Cleaner, more scannable table layout

backend/app/pypi_proxy.py

@@ -17,7 +17,7 @@ from fastapi.responses import StreamingResponse, HTMLResponse
 from sqlalchemy.orm import Session
 
 from .database import get_db
-from .models import UpstreamSource, CachedUrl, Artifact, Project, Package, Tag
+from .models import UpstreamSource, CachedUrl, Artifact, Project, Package, Tag, PackageVersion
 from .storage import S3Storage, get_storage
 from .config import get_env_upstream_sources
 
@@ -30,6 +30,36 @@ PROXY_CONNECT_TIMEOUT = 30.0
 PROXY_READ_TIMEOUT = 60.0
 
 
+def _extract_pypi_version(filename: str) -> Optional[str]:
+    """Extract version from PyPI filename.
+
+    Handles formats like:
+    - cowsay-6.1-py3-none-any.whl
+    - cowsay-1.0.tar.gz
+    - some_package-1.2.3.post1-cp39-cp39-linux_x86_64.whl
+    """
+    # Remove extension
+    if filename.endswith('.whl'):
+        # Wheel: name-version-pytag-abitag-platform.whl
+        parts = filename[:-4].split('-')
+        if len(parts) >= 2:
+            return parts[1]
+    elif filename.endswith('.tar.gz'):
+        # Source: name-version.tar.gz
+        base = filename[:-7]
+        # Find the last hyphen that precedes a version-like string
+        match = re.match(r'^(.+)-(\d+.*)$', base)
+        if match:
+            return match.group(2)
+    elif filename.endswith('.zip'):
+        # Egg/zip: name-version.zip
+        base = filename[:-4]
+        match = re.match(r'^(.+)-(\d+.*)$', base)
+        if match:
+            return match.group(2)
+    return None
+
+
 def _get_pypi_upstream_sources(db: Session) -> list[UpstreamSource]:
     """Get all enabled upstream sources configured for PyPI."""
     # Get database sources
@@ -507,6 +537,7 @@ async def pypi_download_file(
                 project_id=system_project.id,
                 name=normalized_name,
                 description=f"PyPI package: {normalized_name}",
+                format="pypi",
             )
             db.add(package)
             db.flush()
@@ -525,6 +556,23 @@ async def pypi_download_file(
             )
             db.add(tag)
 
+        # Extract and create version
+        version = _extract_pypi_version(filename)
+        if version:
+            existing_version = db.query(PackageVersion).filter(
+                PackageVersion.package_id == package.id,
+                PackageVersion.artifact_id == sha256,
+            ).first()
+            if not existing_version:
+                pkg_version = PackageVersion(
+                    package_id=package.id,
+                    artifact_id=sha256,
+                    version=version,
+                    version_source="filename",
+                    created_by="pypi-proxy",
+                )
+                db.add(pkg_version)
+
         # Cache the URL mapping
         existing_cached = db.query(CachedUrl).filter(CachedUrl.url_hash == url_hash).first()
         if not existing_cached: