feat: add transaction hash search to blockchain explorer and cleanup settlement storage

Blockchain Explorer:
- Add transaction hash search support (64-char hex pattern validation)
- Fetch and display transaction details in modal (hash, type, from/to, amount, fee, block)
- Fix regex escape sequence in block height validation
- Update search placeholder text to mention both search types
- Add blank lines between function definitions for PEP 8 compliance

Settlement Storage:
- Add timedelta import for future

apps/wallet-daemon/tests/conftest.py

@@ -0,0 +1,9 @@
+"""Wallet daemon test configuration"""
+
+import sys
+from pathlib import Path
+
+# Add src to path for imports
+src_path = Path(__file__).parent.parent / "src"
+if str(src_path) not in sys.path:
+    sys.path.insert(0, str(src_path))