docs(tracing): processing PR feedback, clarify endpoint format and add deployment docs

Author: JorisHeadease

docs/CONFIGURATION.md

@@ -45,6 +45,6 @@ Environment variables use the prefix `KNPT_` followed by the configuration path
 | `KNPT_MITZ_TLSKEYPASSWORD`          | `mitz.tlskeypassword`          | Password for .p12/.pfx                                                                                                                                                                                                                                        |
 | `KNPT_MITZ_TLSCAFILE`               | `mitz.tlscafile`               | Path to server certificate                                                                                                                                                                                                                                    |
 | **Tracing / OpenTelemetry**         |                                |                                                                                                                                                                                                                                                               |
-| `KNPT_TRACING_OTLPENDPOINT`         | `tracing.otlpendpoint`         | OTLP HTTP endpoint (host:port) for sending traces. Tracing is enabled when this is set.<br/>Example: `jaeger:4318`.                                                                                                                                           |
+| `KNPT_TRACING_OTLPENDPOINT`         | `tracing.otlpendpoint`         | OTLP collector address as `host:port`. Tracing is enabled when this is set.<br/>Example: `jaeger:4318`.                                                                                                                                           |
 | `KNPT_TRACING_INSECURE`             | `tracing.insecure`             | Use insecure (non-TLS) connection to OTLP endpoint.<br/>Defaults to `true`.                                                                                                                                                                                   |
 | `KNPT_TRACING_SERVICENAME`          | `tracing.servicename`          | Service name reported in traces.<br/>Defaults to `nuts-knooppunt`.                                                                                                                                                                                            |

docs/DEPLOYMENT.md

@@ -87,3 +87,13 @@ The Knooppunt can be deployed with an embedded Nuts node. If a vendor has an exi
 or wants to have the Nuts node deployed separately, the Knooppunt can use that Nuts node instead.
 
 Use [`nuts.enabled`](./CONFIGURATION.md) to configure the embedded or existing Nuts node.
+
+### Tracing
+
+The Knooppunt supports distributed tracing using OpenTelemetry. Traces can be sent to any OTLP-compatible collector (e.g. Jaeger, Grafana Tempo, or a vendor's existing observability platform).
+
+To enable tracing, set [`tracing.otlpendpoint`](./CONFIGURATION.md) to the address of your OTLP collector.
+
+Span names are formatted as `METHOD /path` (e.g. `POST /mcsd/update`). The component can be identified from the path prefix (`/mcsd/*`, `/nvi/*`, `/pdp/*`) and filtered using the `http.target` tag.
+
+See [CONFIGURATION.md](./CONFIGURATION.md) for all tracing options.