Remove code coverage job from CI workflow

- Eliminate Codecov upload failures due to rate limiting
- CI pipeline will now only run: test, rustfmt, clippy, docs, security audit
- All essential code quality checks remain in place

Author: copyleftdev

.github/workflows/ci.yml

@@ -114,21 +114,4 @@ jobs:
     - name: Run audit
       run: cargo audit
 
-  coverage:
-    name: Code Coverage
-    runs-on: ubuntu-latest
-    steps:
-    - uses: actions/checkout@v4
-    - uses: dtolnay/rust-toolchain@stable
-      with:
-        components: llvm-tools-preview
-    - uses: Swatinem/rust-cache@v2
-    - name: Install cargo-llvm-cov
-      run: cargo install cargo-llvm-cov
-    - name: Generate coverage
-      run: cargo llvm-cov --workspace --lcov --output-path lcov.info
-    - name: Upload coverage
-      uses: codecov/codecov-action@v3
-      with:
-        files: lcov.info
-        fail_ci_if_error: true
+