Update logos and add HEZ/PEZ price fallback mechanism

- Update launcher icons (ic_launcher, ic_launcher_round, ic_launcher_foreground)
- Update ic_pezkuwi_logo for all density buckets
- Add priceId for HEZ (hezkurd) and PEZ (pezkuwi) tokens
- Implement price fallback: if CoinGecko price is 0 or missing:
  - HEZ = DOT price / 3
  - PEZ = DOT price / 10

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

pezkuwi-config/chains.json

@@ -39,7 +39,7 @@
         "symbol": "HEZ",
         "precision": 12,
         "name": "Hezkurd",
-        "priceId": null,
+        "priceId": "hezkurd",
         "staking": [
           "relaychain",
           "nomination-pools"
@@ -91,7 +91,7 @@
         "symbol": "HEZ",
         "precision": 12,
         "name": "Hezkurd",
-        "priceId": null,
+        "priceId": "hezkurd",
         "staking": null,
         "type": "Native",
         "icon": "https://pezkuwichain.io/tokens/HEZ.png",
@@ -104,7 +104,7 @@
         "symbol": "PEZ",
         "precision": 12,
         "name": "Pezkuwi",
-        "priceId": null,
+        "priceId": "pezkuwi",
         "staking": null,
         "type": "Statemine",
         "icon": "https://pezkuwichain.io/tokens/PEZ.png",
@@ -168,7 +168,7 @@
         "symbol": "HEZ",
         "precision": 12,
         "name": "Hezkurd",
-        "priceId": null,
+        "priceId": "hezkurd",
         "staking": null,
         "type": "Native",
         "icon": "https://pezkuwichain.io/tokens/HEZ.png",