Add hide component feature, usage indicators, and Docker support

- Add is_hidden field to hide components from configurator
- Add colored dot indicator showing component usage status:
  - Green: available in configurator
  - Cyan: used as source for meta-articles
  - Gray: hidden from configurator
- Optimize price recalculation with caching and skip unchanged
- Show current lot name during price recalculation
- Add Dockerfile (Alpine-based multi-stage build)
- Add docker-compose.yml and .dockerignore

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

.dockerignore

@@ -0,0 +1,33 @@
+# Git
+.git
+.gitignore
+
+# IDE
+.idea
+.vscode
+*.swp
+*.swo
+
+# Build artifacts
+server
+*.exe
+bin/
+
+# Config with secrets
+config.yaml
+
+# Documentation
+*.md
+LICENSE
+
+# Claude
+.claude
+
+# Test files
+*_test.go
+test_*.csv
+test_*.xlsx
+
+# Misc
+.DS_Store
+*.log