style: apply black and isort formatting across entire codebase

- Standardize quote style (single to double quotes)
- Reorder and group imports alphabetically
- Fix line breaks and indentation for consistency
- Apply PEP 8 formatting standards

Also updated Makefile to exclude both venv and .venv from code quality checks.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

models/database/vendor_theme.py

@@ -3,8 +3,9 @@
 Vendor Theme Configuration Model
 Allows each vendor to customize their shop's appearance
 """
-from sqlalchemy import Column, Integer, String, Boolean, Text, JSON, ForeignKey
+from sqlalchemy import JSON, Boolean, Column, ForeignKey, Integer, String, Text
 from sqlalchemy.orm import relationship
+
 from app.core.database import Base
 from models.database.base import TimestampMixin
 
@@ -22,6 +23,7 @@ class VendorTheme(Base, TimestampMixin):
 
     Theme presets available: default, modern, classic, minimal, vibrant
     """
+
     __tablename__ = "vendor_themes"
 
     id = Column(Integer, primary_key=True, index=True)
@@ -29,22 +31,27 @@ class VendorTheme(Base, TimestampMixin):
         Integer,
         ForeignKey("vendors.id", ondelete="CASCADE"),
         nullable=False,
-        unique=True  # ONE vendor = ONE theme
+        unique=True,  # ONE vendor = ONE theme
     )
 
     # Basic Theme Settings
-    theme_name = Column(String(100), default="default")  # default, modern, classic, minimal, vibrant
+    theme_name = Column(
+        String(100), default="default"
+    )  # default, modern, classic, minimal, vibrant
     is_active = Column(Boolean, default=True)
 
     # Color Scheme (JSON for flexibility)
-    colors = Column(JSON, default={
-        "primary": "#6366f1",  # Indigo
-        "secondary": "#8b5cf6",  # Purple
-        "accent": "#ec4899",  # Pink
-        "background": "#ffffff",  # White
-        "text": "#1f2937",  # Gray-800
-        "border": "#e5e7eb"  # Gray-200
-    })
+    colors = Column(
+        JSON,
+        default={
+            "primary": "#6366f1",  # Indigo
+            "secondary": "#8b5cf6",  # Purple
+            "accent": "#ec4899",  # Pink
+            "background": "#ffffff",  # White
+            "text": "#1f2937",  # Gray-800
+            "border": "#e5e7eb",  # Gray-200
+        },
+    )
 
     # Typography
     font_family_heading = Column(String(100), default="Inter, sans-serif")
@@ -59,7 +66,9 @@ class VendorTheme(Base, TimestampMixin):
     # Layout Preferences
     layout_style = Column(String(50), default="grid")  # grid, list, masonry
     header_style = Column(String(50), default="fixed")  # fixed, static, transparent
-    product_card_style = Column(String(50), default="modern")  # modern, classic, minimal
+    product_card_style = Column(
+        String(50), default="modern"
+    )  # modern, classic, minimal
 
     # Custom CSS (for advanced customization)
     custom_css = Column(Text, nullable=True)
@@ -68,14 +77,18 @@ class VendorTheme(Base, TimestampMixin):
     social_links = Column(JSON, default={})  # {facebook: "url", instagram: "url", etc.}
 
     # SEO & Meta
-    meta_title_template = Column(String(200), nullable=True)  # e.g., "{product_name} - {shop_name}"
+    meta_title_template = Column(
+        String(200), nullable=True
+    )  # e.g., "{product_name} - {shop_name}"
     meta_description = Column(Text, nullable=True)
 
     # Relationships - FIXED: back_populates must match the relationship name in Vendor model
     vendor = relationship("Vendor", back_populates="vendor_theme")
 
     def __repr__(self):
-        return f"<VendorTheme(vendor_id={self.vendor_id}, theme_name='{self.theme_name}')>"
+        return (
+            f"<VendorTheme(vendor_id={self.vendor_id}, theme_name='{self.theme_name}')>"
+        )
 
     @property
     def primary_color(self):