feat: initial Pezkuwi Apps rebrand from polkadot-apps

Rebranded terminology:
- Polkadot → Pezkuwi
- Kusama → Dicle
- Westend → Zagros
- Rococo → PezkuwiChain
- Substrate → Bizinikiwi
- parachain → teyrchain

Custom logos with Kurdistan brand colors (#e6007a → #86e62a):
- bizinikiwi-hexagon.svg
- sora-bizinikiwi.svg
- hezscanner.svg
- heztreasury.svg
- pezkuwiscan.svg
- pezkuwistats.svg
- pezkuwiassembly.svg
- pezkuwiholic.svg

packages/react-api/src/util/intervalObservable.ts

@@ -0,0 +1,23 @@
+// Copyright 2017-2025 @pezkuwi/react-api authors & contributors
+// SPDX-License-Identifier: Apache-2.0
+
+import type React from 'react';
+import type { Subscription } from 'rxjs';
+import type { CallState } from '../types.js';
+
+import { interval } from 'rxjs';
+
+const interval$ = interval(500);
+
+export function intervalObservable<Props, State extends CallState> (that: React.Component<Props, State>): Subscription {
+  return interval$.subscribe((): void => {
+    const elapsed = Date.now() - (that.state.callUpdatedAt || 0);
+    const callUpdated = elapsed <= 1500;
+
+    if (callUpdated !== that.state.callUpdated) {
+      that.setState({
+        callUpdated
+      });
+    }
+  });
+}