Complete Hardhat removal - migrate to pure Foundry setup

Remove all Hardhat dependencies while preserving bootAuth server:

🗑️ Removed Hardhat components:
- Config files: hardhat.config.ts, jest.integration.config.js
- Hardhat test files: test/*.test.ts, test/setup.ts
- TypeChain generated types: typechain-types/ directory
- Deployment scripts: scripts/deploy.ts, upgrade.ts, verify.ts
- Build artifacts: .openzeppelin/, cache files
- Dependencies: All @nomicfoundation/hardhat-* packages

✅ Preserved & Updated:
- BootAuth server: src/server.ts, main.ts, types.ts (fully functional)
- EthereumBackend: Updated to use ethers Contract directly (no TypeChain)
- Server tests: Moved main.test.ts to src/ (4 tests passing)
- Foundry setup: All contracts and tests working (32/32 tests passing)
- Package.json: Added Foundry test scripts, removed Hardhat deps
- Documentation: Updated README with server endpoints and usage

🎯 Final architecture:
- Foundry: Smart contract development and testing
- Node.js: HTTP API server for TEE boot validation
- Zero Hardhat dependencies

All tests passing:
- Foundry: 32/32 core contract tests ✅
- Server: 4/4 HTTP API tests ✅
- TypeScript compilation: Success ✅

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <[email protected]>

Author: h4x3rotab

kms/auth-eth/.github/workflows/test.yml

@@ -0,0 +1,40 @@
+name: CI
+
+on:
+  push:
+  pull_request:
+  workflow_dispatch:
+
+env:
+  FOUNDRY_PROFILE: ci
+
+jobs:
+  check:
+    name: Foundry project
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          submodules: recursive
+
+      - name: Install Foundry
+        uses: foundry-rs/foundry-toolchain@v1
+
+      - name: Show Forge version
+        run: |
+          forge --version
+
+      - name: Run Forge fmt
+        run: |
+          forge fmt --check
+        id: fmt
+
+      - name: Run Forge build
+        run: |
+          forge build --sizes
+        id: build
+
+      - name: Run Forge tests
+        run: |
+          forge test -vvv
+        id: test