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>

build-for-dev.sh

@@ -0,0 +1,9 @@
+#!/bin/bash
+# Build the library for development (used by demo)
+
+set -e
+
+echo "Building @sda/flair-elements-ui for development..."
+npm run build
+
+echo "Build complete! Library available at dist/"