Initial commit: notification-elements-demo app

Interactive Angular 19 demo for @sda/notification-elements-ui with
6 sections: Bell & Feed, Notification Center, Inbox, Comments &
Threads, Mention Input, and Full-Featured layout. Includes mock
data, dark mode toggle, and real-time event log.

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

node_modules/thingies/lib/LruCache.js

@@ -0,0 +1,106 @@
+"use strict";
+Object.defineProperty(exports, "__esModule", { value: true });
+exports.LruCache = void 0;
+class LruCache {
+    constructor(limit = 1000) {
+        this.limit = limit;
+        this.head = undefined;
+        this.tail = undefined;
+        this.map = Object.create(null);
+        this.capacity = limit | 0;
+    }
+    get size() {
+        return this.limit - this.capacity;
+    }
+    set(key, value) {
+        const node = this.map[key];
+        if (node) {
+            this.pop(node);
+            node.v = value;
+            this.push(node);
+        }
+        else {
+            if (!this.capacity) {
+                const head = this.head;
+                if (head) {
+                    this.pop(head);
+                    delete this.map[head.k];
+                    this.capacity++;
+                }
+            }
+            this.capacity--;
+            const node = new LruNode(key, value);
+            this.map[key] = node;
+            this.push(node);
+        }
+    }
+    get(key) {
+        const node = this.map[key];
+        if (!node)
+            return;
+        if (this.tail !== node) {
+            this.pop(node);
+            this.push(node);
+        }
+        return node.v;
+    }
+    peek(key) {
+        const node = this.map[key];
+        return node instanceof LruNode ? node.v : undefined;
+    }
+    has(key) {
+        return key in this.map;
+    }
+    clear() {
+        this.head = undefined;
+        this.tail = undefined;
+        this.map = Object.create(null);
+        this.capacity = this.limit;
+    }
+    keys() {
+        return Object.keys(this.map);
+    }
+    del(key) {
+        const node = this.map[key];
+        if (node instanceof LruNode) {
+            this.pop(node);
+            delete this.map[key];
+            ++this.capacity;
+            return true;
+        }
+        return false;
+    }
+    pop(node) {
+        const l = node.l;
+        const r = node.r;
+        if (this.head === node)
+            this.head = r;
+        else
+            l.r = r;
+        if (this.tail === node)
+            this.tail = l;
+        else
+            r.l = l;
+        // node.l = undefined;
+        // node.r = undefined;
+    }
+    push(node) {
+        const tail = this.tail;
+        if (tail) {
+            tail.r = node;
+            node.l = tail;
+        }
+        else
+            this.head = node;
+        this.tail = node;
+    }
+}
+exports.LruCache = LruCache;
+class LruNode {
+    constructor(k, v) {
+        this.k = k;
+        this.v = v;
+        this.l = undefined;
+        this.r = undefined;
+    }
+}