Migrate logging to go-mana-component; delete logging/ package

Replaces the flat key-value logging scheme with component-based structured
logging via go-mana-component. Each layer (pool, worker, connection) builds
its own component identity and derives a *slog.Logger from a caller-supplied
slog.Handler.

- Delete logging/ package (logging.go, logging_test.go)
- Strip LoggingEnabled and LogLevel from ConnectionConfig, PoolConfig,
 WorkerConfig; remove associated option funcs
- Change NewConnection and NewConnectionFromSocket to accept ctx and
 slog.Handler instead of *slog.Logger; constructors build component
 identity via MustNew/MustExtend internally
- Change WorkerFactory, NewWorker, connect, and RunDialer to carry
 slog.Handler; remove PoolPlugin.Handler
- Change NewPool to establish pool component identity via MustNew;
 remove pool_id field, PoolPlugin.ID, and ErrInvalidPoolID
- Fix data race in MockSlogHandler: WithAttrs now shares parent mutex
 pointer rather than allocating a new one per child
- Run go fix

honeybeetest/mocks.go

@@ -98,7 +98,7 @@ func (m *MockSocket) SetPongHandler(h func(s string) error) {
 type MockSlogHandler struct {
 	records *[]slog.Record
 	attrs   []slog.Attr
-	mu      sync.RWMutex
+	mu      *sync.RWMutex
 }
 
 func NewMockSlogHandler() *MockSlogHandler {
@@ -106,6 +106,7 @@ func NewMockSlogHandler() *MockSlogHandler {
 	return &MockSlogHandler{
 		records: &records,
 		attrs:   make([]slog.Attr, 0),
+		mu:      &sync.RWMutex{},
 	}
 }
 
@@ -126,6 +127,7 @@ func (m *MockSlogHandler) WithAttrs(attrs []slog.Attr) slog.Handler {
 	defer m.mu.RUnlock()
 	return &MockSlogHandler{
 		records: m.records, // shared records slice
+		mu:      m.mu,      // shared mutex
 		attrs:   append(m.attrs, attrs...),
 	}
 }