v2.0.0: error-channel APIs, correctness fixes, and server hardening

BREAKING CHANGES:
- Guard interface: Guard(ctx Ctx) error; returning error short-circuits
  (subsequent guards and the method no longer execute)
- Wired[T]() (*T, error); New() may return error; failed wiring is sticky
- BindService/BindGuard/BindRoute return error; routes accept guards
  (guards receive merged query/form params as Ctx.State)
- registration panics after Start; Ctx.Ip honors X-Forwarded-For/X-Real-IP
- internal errors sanitized to fixed client messages

FIXES:
- int64 precision loss: /cell data decoded from raw JSON bytes and
  responses serialized with json.Number (no float64 round-trip)
- enum values range-checked before uint8 conversion (256 no longer
  truncates to 0 and slips through)
- logger: files failing name parsing are no longer deleted; log channel
  never blocks request goroutines; ConfigLogger is race-free;
  logWriterWorker unlock bug fixed
- stream writer panics recovered (process no longer crashes);
  streamDone closed exactly once
- generated Go client emits definitions for pointer-to-enum/struct fields
- anonymous structs rejected at registration; isPrivate safe on empty names
- removed dead Result.Id and RequestInfo.Type

ADDITIONS:
- graceful shutdown (Shutdown), StartOn, server timeouts by default
  (Read 60s/Idle 120s/Write off), SetTimeouts/SetMaxConcurrency
- big-int-safe JSON in the generated TS client (>2^53 as BigInt)
- example/ demo services and cmd/genexample artifact generator

fun_test.go

@@ -29,8 +29,9 @@ var guardHit = false
 
 type TestGuard struct{}
 
-func (g *TestGuard) Guard(ctx Ctx) {
+func (g *TestGuard) Guard(ctx Ctx) error {
 	guardHit = true
+	return nil
 }
 
 func (s *TestSvc) Hello(dto TestDto) (string, error) {
@@ -58,7 +59,9 @@ func (s *TestSvc) Count(dto TestDto) (*Stream, error) {
 func TestCtxBoxInject(t *testing.T) {
 	f := New()
 	guardHit = false
-	f.BindService(&TestSvc{}, &TestGuard{})
+	if err := f.BindService(&TestSvc{}, &TestGuard{}); err != nil {
+		t.Fatal(err)
+	}
 	c := &Ctx{Ip: "1.2.3.4", MethodName: "Hello", ServiceName: "TestSvc"}
 	data := map[string]any{"name": "tom", "age": 1}
 	c.Data = &data
@@ -79,7 +82,9 @@ func TestCtxBoxInject(t *testing.T) {
 
 func TestCheckDtoRequired(t *testing.T) {
 	f := New()
-	f.BindService(&TestSvc{})
+	if err := f.BindService(&TestSvc{}); err != nil {
+		t.Fatal(err)
+	}
 	c := &Ctx{Ip: "x", MethodName: "Hello", ServiceName: "TestSvc"}
 	data := map[string]any{"age": 1}
 	c.Data = &data
@@ -94,7 +99,9 @@ func TestCheckDtoRequired(t *testing.T) {
 
 func TestGenCode(t *testing.T) {
 	isolateGeneratorGlobals(t)
-	GetFun().BindService(&TestSvc{})
+	if err := GetFun().BindService(&TestSvc{}); err != nil {
+		t.Fatal(err)
+	}
 	SetOutput(t.TempDir())
 	GenCode(GenGo{}, GenTs{})
 	if _, err := os.Stat(filepath.Join(getDirectory(), "go", "test_svc.go")); err != nil {
@@ -107,7 +114,9 @@ func TestGenCode(t *testing.T) {
 
 func startServer(t *testing.T, port uint16) *Fun {
 	f := New()
-	f.BindService(&TestSvc{})
+	if err := f.BindService(&TestSvc{}); err != nil {
+		t.Fatal(err)
+	}
 	go f.Start(port)
 	time.Sleep(300 * time.Millisecond)
 	return f