feat: major project restructure - move Django to backend dir and fix critical imports

- Restructure project: moved Django backend to backend/ directory
- Add frontend/ directory for future Next.js application
- Add shared/ directory for common resources
- Fix critical Django import errors:
  - Add missing sys.path modification for apps directory
  - Fix undefined CATEGORY_CHOICES imports in rides module
  - Fix media migration undefined references
  - Remove unused imports and f-strings without placeholders
- Install missing django-environ dependency
- Django server now runs without ModuleNotFoundError
- Update .gitignore and README for new structure
- Add pnpm workspace configuration for monorepo setup

static/js/location-search.js

@@ -1,54 +0,0 @@
-document.addEventListener('DOMContentLoaded', function() {
-    const useLocationBtn = document.getElementById('use-my-location');
-    const latInput = document.getElementById('lat-input');
-    const lngInput = document.getElementById('lng-input');
-    const locationInput = document.getElementById('location-input');
-
-    if (useLocationBtn && 'geolocation' in navigator) {
-        useLocationBtn.addEventListener('click', function() {
-            this.textContent = '📍 Getting location...';
-            this.disabled = true;
-            
-            navigator.geolocation.getCurrentPosition(
-                function(position) {
-                    latInput.value = position.coords.latitude;
-                    lngInput.value = position.coords.longitude;
-                    locationInput.value = `${position.coords.latitude.toFixed(6)}, ${position.coords.longitude.toFixed(6)}`;
-                    useLocationBtn.textContent = '✅ Location set';
-                    setTimeout(() => {
-                        useLocationBtn.textContent = '📍 Use My Location';
-                        useLocationBtn.disabled = false;
-                    }, 2000);
-                },
-                function(error) {
-                    useLocationBtn.textContent = '❌ Location failed';
-                    console.error('Geolocation error:', error);
-                    setTimeout(() => {
-                        useLocationBtn.textContent = '📍 Use My Location';
-                        useLocationBtn.disabled = false;
-                    }, 2000);
-                }
-            );
-        });
-    } else if (useLocationBtn) {
-        useLocationBtn.style.display = 'none';
-    }
-
-    // Autocomplete for location search
-    if (locationInput) {
-        locationInput.addEventListener('input', function() {
-            const query = this.value;
-            if (query.length < 3) {
-                return;
-            }
-
-            fetch(`/search/location/suggestions/?q=${query}`)
-                .then(response => response.json())
-                .then(data => {
-                    // This is a simplified example. A more robust solution would use a library like Awesomplete or build a custom dropdown.
-                    console.log('Suggestions:', data.suggestions);
-                })
-                .catch(error => console.error('Error fetching suggestions:', error));
-        });
-    }
-});