A policy type controls how the enrich index is created and
the query executed against the match field. Currently there
is a single policy type (`exact_match`). In the near future
more policy types will be added and different policy may have
different configuration options.
For this reason type should be a json object instead of a string field:
```
{
"exact_match": {
...
}
}
```
instead of:
```
{
"type": "exact_match",
...
}
```
This will make streaming parsing of enrich policies easier as in the
new format, the parsing code can know ahead what configuration fields
to expect. In the latter format that is not possible if the type field
appears not as the first field.
Relates to #32789
This commit adds permissions validation on the indices provided in the
enrich policy. These indices should be validated at store time so as not
to have cryptic error messages in the event the user does not have
permissions to access said indices.
This commit adds the manage_enrich privilege, which grants access to all
of the enrich processor lifecycle actions. In addition this commit also
creates a role which grants access to the generated indices.
Relates #41939
Co-authored-by: Martijn van Groningen <martijn.v.groningen@gmail.com>
