feat: Add comprehensive documentation suite and reorganize project structure

- Created complete documentation in docs/ directory
- Added PROJECT_OVERVIEW.md with feature highlights and getting started guide
- Added ARCHITECTURE.md with system design and technical details
- Added SECURITY.md with comprehensive security implementation guide
- Added DEVELOPMENT.md with development workflows and best practices
- Added DEPLOYMENT.md with production deployment instructions
- Added API.md with complete REST API documentation
- Added CONTRIBUTING.md with contribution guidelines
- Added CHANGELOG.md with version history and migration notes
- Reorganized all documentation files into docs/ directory for better organization
- Updated README.md with proper documentation links and quick navigation
- Enhanced project structure with professional documentation standards

f_scripts/shared/datepicker/date-range-picker.css

@@ -0,0 +1,82 @@
+.dr-cals {
+  display: flex;
+  justify-content: space-between;
+  background: white;
+  box-shadow: 8px 8px 32px -16px rgba(0, 0, 0, 0.5);
+  padding-top: 6px;
+  position: relative;
+  border-radius: 6px;
+  overflow: hidden;
+}
+
+.dr-cals:before {
+  content: ' ';
+  height: 6px;
+  position: absolute;
+  top: 0;
+  left: 0;
+  right: 0;
+  background: #3B99FC;
+  background: linear-gradient(-90deg, #3B99FC 0%, #8AEFC8 100%);
+}
+
+.dr-cals .dp-edge-day {
+  visibility: hidden;
+}
+
+.dr-cals .dp-cal-footer {
+  display: none;
+}
+
+.dr-cals .dp {
+  border: 0;
+}
+
+.dr-cals .dp-permanent {
+  max-width: 300px;
+}
+
+.dr-cals .dp-selected:focus,
+.dr-cals .dp-selected,
+.dr-cals .dp-current:focus,
+.dr-cals .dp-current {
+  background: transparent;
+  color: inherit;
+  border-radius: 0;
+}
+
+.dr-cal-end .dp {
+  border-left: 8px solid #F5F5F5;
+}
+
+.dr-cal-start .dp-next,
+.dr-cal-end .dp-prev {
+  visibility: hidden;
+}
+
+.dr-cals .dp-current:hover,
+.dr-cals .dr-in-range:hover,
+.dr-cals .dr-in-range:focus,
+.dr-cals .dr-in-range {
+  background: #75BCFC;
+  color: white;
+  border-radius: 0;
+}
+
+.dr-cals .dr-selected:hover,
+.dr-cals .dr-selected:focus,
+.dr-cals .dr-selected {
+  background: #3B99FC;
+  color: white;
+  border-radius: 0;
+}
+
+@media (max-width: 616px), (max-height: 480px) {
+  .dr-cal-end {
+    display: none;
+  }
+
+  .dr-cal-start .dp-next {
+    visibility: visible;
+  }
+}