Add CI Pipeline: build, test, clippy, fmt check

- ci.yml: main workflow with build, test, clippy, fmt
- macos-build: macOS-specific job
- security-audit: dedicated security test job
- Remove old linux-test.yml

.github/workflows/ci.yml

@@ -0,0 +1,53 @@
+name: CI
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+    branches: [main]
+
+jobs:
+  build-and-test:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      
+      - name: Install Rust
+        uses: actions-rust-lang/setup-rust-toolchain@v1
+        
+      - name: Build
+        run: cargo build --verbose
+        
+      - name: Run tests
+        run: cargo test --verbose
+        
+      - name: Run clippy
+        run: cargo clippy -- -D warnings
+        
+      - name: Check formatting
+        run: cargo fmt --check
+
+  macos-build:
+    runs-on: macos-latest
+    steps:
+      - uses: actions/checkout@v4
+      
+      - name: Install Rust
+        uses: actions-rust-lang/setup-rust-toolchain@v1
+        
+      - name: Build
+        run: cargo build --verbose
+        
+      - name: Run tests
+        run: cargo test --verbose
+
+  security-audit:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      
+      - name: Install Rust
+        uses: actions-rust-lang/setup-rust-toolchain@v1
+        
+      - name: Run security tests
+        run: cargo test --lib security_audit --verbose