mt2exm: fix jsoncpp API misuse

jengelh · jengelh · commit 6dbdeb3c5092 · 2025-10-21T13:54:31.000+02:00
```
mt2exm: Exception: in Json::Value::clear(): requires complex value
```

References: GXL-645, DESK-4131
diff --git a/tools/mt2exm.cpp b/tools/mt2exm.cpp
@@ -421,7 +421,7 @@ static int exm_create_msg(uint64_t parent_fld, MESSAGE_CONTENT *ctnt,
 		return -EIO;
 	}
 	auto djson = json_to_str(digest);
-	digest["file"].clear();
+	digest.removeMember("file");
 
 	uint64_t outmid = 0, outcn = 0;
 	if (!exmdb_client->write_message(g_storedir, CP_UTF8, parent_fld,

Original file line number	Diff line number	Diff line change
`@@ -421,7 +421,7 @@ static int exm_create_msg(uint64_t parent_fld, MESSAGE_CONTENT *ctnt,`
`421`	`421`	`return -EIO;`
`422`	`422`	`}`
`423`	`423`	`auto djson = json_to_str(digest);`
`424`		`- digest["file"].clear();`
	`424`	`+ digest.removeMember("file");`
`425`	`425`
`426`	`426`	`uint64_t outmid = 0, outcn = 0;`
`427`	`427`	`if (!exmdb_client->write_message(g_storedir, CP_UTF8, parent_fld,`