Open telemetry integration (#3972)

This PR adds opentelemetry and chi wrapper to have basic instrumentation

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## Draft release notes
<!--URL:https://codeberg.org/forgejo/forgejo-->
- Features
  - [PR](https://codeberg.org/forgejo/forgejo/pulls/3972): <!--number 3972 --><!--line 0 --><!--description YWRkIHN1cHBvcnQgZm9yIGJhc2ljIHJlcXVlc3QgdHJhY2luZyB3aXRoIG9wZW50ZWxlbWV0cnk=-->add support for basic request tracing with opentelemetry<!--description-->
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Reviewed-on: https://codeberg.org/forgejo/forgejo/pulls/3972
Reviewed-by: Earl Warren <earl-warren@noreply.codeberg.org>
Co-authored-by: TheFox0x7 <thefox0x7@gmail.com>
Co-committed-by: TheFox0x7 <thefox0x7@gmail.com>

routers/common/middleware.go

@@ -18,6 +18,7 @@ import (
 	"gitea.com/go-chi/session"
 	"github.com/chi-middleware/proxy"
 	chi "github.com/go-chi/chi/v5"
+	"github.com/riandyrn/otelchi"
 )
 
 // ProtocolMiddlewares returns HTTP protocol related middlewares, and it provides a global panic recovery
@@ -68,6 +69,9 @@ func ProtocolMiddlewares() (handlers []any) {
 	if setting.IsAccessLogEnabled() {
 		handlers = append(handlers, context.AccessLogger())
 	}
+	if setting.IsOpenTelemetryEnabled() {
+		handlers = append(handlers, otelchi.Middleware("forgejo"))
+	}
 
 	return handlers
 }