ci: Add comprehensive CI quality gates

- New ci.yml workflow: rust-format, clippy, rust-test, security-audit, frontend-lint
- rustfmt.toml: strict formatting rules (edition 2021, max_width 100, grouped imports)
- clippy.toml: lint configuration with complexity thresholds
- eslint.config.js: ESLint 9 flat config for TypeScript/React
- build.yml: now only triggers on v* tags (ci.yml handles master/PR)
- package.json: updated lint script for ESLint 9 flat config

Quality gates run on every push to master and every PR:
1. Rust Format Check (cargo fmt --check --all)
2. Clippy Lints (pedantic + deny warnings)
3. Rust Unit Tests (cargo test --workspace --all-features)
4. Security Audit (cargo audit)
5. Frontend Lint (ESLint + TypeScript type check)

clippy.toml

@@ -0,0 +1,11 @@
+# Linux Patch Manager - Clippy Lint Configuration
+# Run: cargo clippy -- -D warnings (CI) or cargo clippy (local)
+
+# Deny all warnings in CI - warnings become errors
+cognitive-complexity-threshold = 30
+
+# Type complexity limits
+type-complexity-threshold = 300
+
+# Single character binding names allowed for common patterns (i, j, k, e, f, etc.)
+allow-single-char-binding-names = ["i", "j", "k", "n", "e", "f", "r", "w", "x", "y", "z"]