fix: resolve remaining CI issues — services, hardhat, Rust, mypy

Service health checks:
- Exchange API uses /api/health not /health — updated test script
  and workflow wait loops to check /api/health as fallback
- Increased wait time to 2s intervals, 15 retries for service readiness
- Performance tests now hit /health endpoints (not root /)

Hardhat compilation:
- aitbc-token was missing peer deps for @nomicfoundation/hardhat-toolbox
- Installed all 11 required peer packages (ethers, typechain, etc.)
- Contracts now compile (19 Solidity files) and all 17 tests pass

Rust workflow:
- Fixed HOME mismatch: gitea-runner HOME=/opt/gitea-runner vs
  euid root HOME=/root — explicitly set HOME=/root in all steps
- Set RUSTUP_HOME and CARGO_HOME for consistent toolchain location

Mypy type annotations (aitbc-agent-sdk):
- agent.py: narrow key types to RSA (isinstance check before sign/verify),
  fix supported_models Optional type, add __post_init__ return type
- compute_provider.py: add return types to all methods, declare
  pricing_model/dynamic_pricing attrs, rename register→create_provider
  to avoid signature conflict with parent, fix Optional safety
- swarm_coordinator.py: add return types to all 8 untyped methods

scripts/ci/test_api_endpoints.py

@@ -10,7 +10,7 @@ import sys
 # Service ports (must match systemd config)
 SERVICES = {
     "coordinator": {"url": "http://localhost:8000", "endpoints": ["/", "/health", "/info"]},
-    "exchange": {"url": "http://localhost:8001", "endpoints": ["/", "/health", "/info"]},
+    "exchange": {"url": "http://localhost:8001", "endpoints": ["/", "/api/health", "/health", "/info"]},
     "wallet": {"url": "http://localhost:8003", "endpoints": ["/", "/health", "/wallets"]},
     "blockchain_rpc": {"url": "http://localhost:8006", "endpoints": []},
 }
@@ -105,9 +105,9 @@ def main():
 
     print("\n⚡ Performance tests...")
     perf = test_performance([
-        ("Coordinator", "http://localhost:8000/"),
-        ("Exchange", "http://localhost:8001/"),
-        ("Wallet", "http://localhost:8003/"),
+        ("Coordinator", "http://localhost:8000/health"),
+        ("Exchange", "http://localhost:8001/api/health"),
+        ("Wallet", "http://localhost:8003/health"),
     ])
     all_results["performance"] = perf