docs(sync): document the configurable sync listener port

Reflect the new `ports.sync` config field / `NODEDB_PORT_SYNC` env
override (default 9090, always on) introduced for the sync listener:
list it alongside the other port settings in getting-started.md, and
note in protocols.md that the sync protocol port is now configurable
rather than fixed.

Author: emanzx

docs/getting-started.md

@@ -223,6 +223,7 @@ log_format = "text"               # "text" or "json"
 native = 6433                     # Always-on protocols have defaults
 pgwire = 6432
 http = 6480
+sync = 9090                       # Always on
 resp = 6381                       # Optional: set to enable, omit to disable
 ilp = 8086                        # Optional: set to enable, omit to disable
 
@@ -244,6 +245,7 @@ ilp = false                       # Example: disable TLS for ILP ingest
 | `ports.native`     | `NODEDB_PORT_NATIVE`      | `6433`                                                |
 | `ports.pgwire`     | `NODEDB_PORT_PGWIRE`      | `6432`                                                |
 | `ports.http`       | `NODEDB_PORT_HTTP`        | `6480`                                                |
+| `ports.sync`       | `NODEDB_PORT_SYNC`        | `9090`                                                |
 | `ports.resp`       | `NODEDB_PORT_RESP`        | disabled                                              |
 | `ports.ilp`        | `NODEDB_PORT_ILP`         | disabled                                              |
 | `data_dir`         | `NODEDB_DATA_DIR`         | `~/.nodedb/data` (binary), `/var/lib/nodedb` (Docker) |

docs/protocols.md

@@ -223,7 +223,7 @@ SELECT * FROM cpu WHERE ts > now() - INTERVAL '1 hour';
 
 CRDT sync protocol for NodeDB-Lite clients (mobile, WASM, desktop). Bidirectional delta exchange over WebSocket.
 
-**Port:** 9090 (default)
+**Port:** 9090 (default). Configurable via `[server.ports] sync` or `NODEDB_PORT_SYNC`.
 
 **Flow:**
 
@@ -256,6 +256,7 @@ host = "127.0.0.1"
 pgwire = 6432       # Always on
 native = 6433       # Always on
 http = 6480         # Always on
+sync = 9090         # Always on
 resp = 6381         # Set to enable (omit to disable)
 ilp = 8086          # Set to enable (omit to disable)
 
@@ -269,7 +270,7 @@ resp = true
 ilp = false         # Example: disable TLS for ILP ingest
 ```
 
-Environment variables override config: `NODEDB_PORT_PGWIRE`, `NODEDB_PORT_NATIVE`, `NODEDB_PORT_HTTP`, `NODEDB_PORT_RESP`, `NODEDB_PORT_ILP`.
+Environment variables override config: `NODEDB_PORT_PGWIRE`, `NODEDB_PORT_NATIVE`, `NODEDB_PORT_HTTP`, `NODEDB_PORT_SYNC`, `NODEDB_PORT_RESP`, `NODEDB_PORT_ILP`.
 
 ## Native Protocol Opcodes (SDK Reference)