merge: consolidate config/ and configs/ directories into single config/

DIRECTORY MERGE:
- Merged /cli/configs/ into /cli/config/
- Eliminated duplicate configuration directories
- Unified all configuration files in single location

MERGED FILES:
✅ healthcare_chain_config.yaml → config/
✅ multichain_config.yaml → config/
✅ genesis_ait_devnet_proper.yaml (already in config/)
✅ genesis_multi_chain_dev.yaml (already in config/)

DIRECTORY STRUCTURE AFTER:
/cli/config/
├── __init__.py                    # Python config module
├── genesis_ait_devnet_proper.yaml
├── genesis_multi_chain_dev.yaml
├── healthcare_chain_config.yaml   # Moved from configs/
└── multichain_config.yaml          # Moved from configs/

BENEFITS:
✅ Single source of truth for all configuration
✅ No duplicate directory confusion
✅ Easier maintenance and organization
✅ All YAML configs accessible from Python module
✅ No hardcoded path references to update

VERIFICATION:
✅ Python imports still work: 'from config import get_config'
✅ YAML files accessible and loadable
✅ No breaking changes to existing code
✅ CLI functionality preserved

STATUS: Complete - No wiring changes needed

cli/config/multichain_config.yaml

@@ -0,0 +1,26 @@
+# Multi-chain configuration for AITBC CLI
+nodes:
+  default-node:
+    id: default-node
+    endpoint: http://localhost:8545
+    timeout: 30
+    retry_count: 3
+    max_connections: 10
+  
+  aitbc-main:
+    id: aitbc-main
+    endpoint: http://localhost:8546
+    timeout: 30
+    retry_count: 3
+    max_connections: 10
+
+chains:
+  default_gas_limit: 10000000
+  default_gas_price: 20000000000
+  max_block_size: 1048576
+  backup_path: ./backups
+  max_concurrent_chains: 100
+
+logging_level: INFO
+enable_caching: true
+cache_ttl: 300