feat: ja4-platform monorepo — 5 services unified, tests & RPM builds standardized

Services:
- ja4sentinel: TLS/JA4 fingerprint capture daemon (Go, libpcap)
- logcorrelator: JA4 log correlation engine (Go, ClickHouse)
- mod_reqin_log: Apache module (C, JSON request logging)
- bot_detector: ML bot detection pipeline (Python)
- dashboard: FastAPI/Streamlit analytics UI (Python)

Shared libraries:
- shared/go/ja4common: logger, config, shutdown, ipfilter (Go module)
- shared/python/ja4_common: ClickHouseClient, ClickHouseSettings (Python package)
- shared/clickhouse/: canonical SQL migrations (10 files)

Build & packaging:
- Unified 3-stage Dockerfile.package for Go RPMs (el8/el9/el10)
- go.work workspace linking sentinel, correlator, ja4common
- Makefile with test-all, build-all, rpm-* targets

Fixes applied:
- go.work: 1.21 → 1.24.6 (required by sentinel)
- correlator Dockerfiles: golang:1.21 → golang:1.24
- replace directives in go.mod for ja4common local path
- pyproject.toml: setuptools.backends → setuptools.build_meta
- Removed static libpcap linking (unavailable on Rocky 9)
- Fixed data races in output/writers_test.go (sync.Mutex + atomic.Int32)
- Rewrote corrupted test files (logger_test.go × 2)

Test coverage:
- correlator: 67.1% total (unixsocket 80.5%, config 91.7%, app 83.3%, multi 87.7%, stdout 100%)
- sentinel: all 10 packages pass (api, capture, config, fingerprint, ipfilter, logging, output, tlsparse)

Documentation:
- README.md + docs/ (architecture, development, 5 services, shared libs, DB schema & migrations)

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

shared/go/ja4common/shutdown/handler_test.go

@@ -0,0 +1,133 @@
+package shutdown
+
+import (
+	"context"
+	"errors"
+	"sync/atomic"
+	"syscall"
+	"testing"
+	"time"
+)
+
+type mockLogger struct {
+	infoMsgs  []string
+	errorMsgs []string
+}
+
+func (m *mockLogger) Info(msg string)          { m.infoMsgs = append(m.infoMsgs, msg) }
+func (m *mockLogger) Error(msg string, _ error) { m.errorMsgs = append(m.errorMsgs, msg) }
+
+func TestHandle_RunsHooks(t *testing.T) {
+	ctx, cancel := context.WithCancel(context.Background())
+	logger := &mockLogger{}
+	var hookCalled int32
+
+	hooks := []Hook{
+		{
+			Name: "test-hook",
+			Fn: func() error {
+				atomic.StoreInt32(&hookCalled, 1)
+				return nil
+			},
+		},
+	}
+
+	done := make(chan struct{})
+	go func() {
+		Handle(ctx, cancel, hooks, logger)
+		close(done)
+	}()
+
+	// Send SIGTERM to trigger shutdown
+	time.Sleep(50 * time.Millisecond)
+	p, _ := syscall.Getpid(), 0
+	syscall.Kill(p, syscall.SIGTERM)
+
+	select {
+	case <-done:
+	case <-time.After(3 * time.Second):
+		t.Fatal("Handle did not return within timeout")
+	}
+
+	if atomic.LoadInt32(&hookCalled) != 1 {
+		t.Error("hook was not called")
+	}
+}
+
+func TestHandle_HookError_ContinuesOtherHooks(t *testing.T) {
+	ctx, cancel := context.WithCancel(context.Background())
+	logger := &mockLogger{}
+	var secondCalled int32
+
+	hooks := []Hook{
+		{
+			Name: "failing-hook",
+			Fn:   func() error { return errors.New("hook error") },
+		},
+		{
+			Name: "second-hook",
+			Fn: func() error {
+				atomic.StoreInt32(&secondCalled, 1)
+				return nil
+			},
+		},
+	}
+
+	done := make(chan struct{})
+	go func() {
+		Handle(ctx, cancel, hooks, logger)
+		close(done)
+	}()
+
+	time.Sleep(50 * time.Millisecond)
+	syscall.Kill(syscall.Getpid(), syscall.SIGTERM)
+
+	select {
+	case <-done:
+	case <-time.After(3 * time.Second):
+		t.Fatal("Handle did not return within timeout")
+	}
+
+	if atomic.LoadInt32(&secondCalled) != 1 {
+		t.Error("second hook should still run after first hook error")
+	}
+	if len(logger.errorMsgs) == 0 {
+		t.Error("error should be logged for failing hook")
+	}
+}
+
+func TestHandle_ContextCancel(t *testing.T) {
+	ctx, cancel := context.WithCancel(context.Background())
+	logger := &mockLogger{}
+	var hookCalled int32
+
+	hooks := []Hook{
+		{
+			Name: "ctx-hook",
+			Fn: func() error {
+				atomic.StoreInt32(&hookCalled, 1)
+				return nil
+			},
+		},
+	}
+
+	done := make(chan struct{})
+	go func() {
+		Handle(ctx, cancel, hooks, logger)
+		close(done)
+	}()
+
+	// Cancel context directly instead of sending signal
+	time.Sleep(50 * time.Millisecond)
+	cancel()
+
+	select {
+	case <-done:
+	case <-time.After(3 * time.Second):
+		t.Fatal("Handle did not return within timeout after context cancel")
+	}
+
+	if atomic.LoadInt32(&hookCalled) != 1 {
+		t.Error("hook should run on context cancel")
+	}
+}