feat: add @sda/flair-elements-ui library

Angular 19+ standalone library with 61 components, 15 directives,
and 8 services for decorative visual effects, animations, and
micro-interactions.

Components include particle systems, flow fields, aurora effects,
tilt/holographic/spotlight cards, text effects, dividers, scroll
animations, generative art, celebrations, image treatments,
morphing shapes, terminal output, and pattern textures.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

.gitignore

@@ -0,0 +1,38 @@
+# Dependencies
+node_modules/
+package-lock.json
+
+# Build outputs
+dist/
+out-tsc/
+*.tsbuildinfo
+
+# IDE
+.vscode/
+.idea/
+*.swp
+*.swo
+*~
+
+# OS
+.DS_Store
+Thumbs.db
+
+# Angular
+.angular/
+*.ngfactory.ts
+*.ngsummary.json
+*.metadata.json
+
+# Testing
+coverage/
+.nyc_output/
+
+# Misc
+*.log
+npm-debug.log*
+yarn-debug.log*
+yarn-error.log*
+lerna-debug.log*
+.npm
+.eslintcache