Fix max-indexes config operational default value and max-value overlap.

[Shivshankar-Reddy]

As part of #214, the max-indexes intended default value is 10 and max value suppossed be max-limit. However, both values are hard coded to 10 and if we want to change beyond 10 it will fail as below.

127.0.0.1:6379>
127.0.0.1:6379> FT.CREATE idx1 SCHEMA vec VECTOR HNSW 6 TYPE FLOAT32 DIM 4 DISTANCE_METRIC L2 tag TAG
OK
127.0.0.1:6379> FT.CREATE idx2 SCHEMA vec VECTOR HNSW 6 TYPE FLOAT32 DIM 4 DISTANCE_METRIC L2 tag TAG
OK
127.0.0.1:6379> FT.CREATE idx3 SCHEMA vec VECTOR HNSW 6 TYPE FLOAT32 DIM 4 DISTANCE_METRIC L2 tag TAG
OK
127.0.0.1:6379> FT.CREATE idx4 SCHEMA vec VECTOR HNSW 6 TYPE FLOAT32 DIM 4 DISTANCE_METRIC L2 tag TAG
OK
127.0.0.1:6379> FT.CREATE idx5 SCHEMA vec VECTOR HNSW 6 TYPE FLOAT32 DIM 4 DISTANCE_METRIC L2 tag TAG
OK
127.0.0.1:6379> FT.CREATE idx6 SCHEMA vec VECTOR HNSW 6 TYPE FLOAT32 DIM 4 DISTANCE_METRIC L2 tag TAG
OK
127.0.0.1:6379> FT.CREATE idx7 SCHEMA vec VECTOR HNSW 6 TYPE FLOAT32 DIM 4 DISTANCE_METRIC L2 tag TAG
OK
127.0.0.1:6379> FT.CREATE idx8 SCHEMA vec VECTOR HNSW 6 TYPE FLOAT32 DIM 4 DISTANCE_METRIC L2 tag TAG
OK
127.0.0.1:6379> FT.CREATE idx9 SCHEMA vec VECTOR HNSW 6 TYPE FLOAT32 DIM 4 DISTANCE_METRIC L2 tag TAG
OK
127.0.0.1:6379> FT.CREATE idx10 SCHEMA vec VECTOR HNSW 6 TYPE FLOAT32 DIM 4 DISTANCE_METRIC L2 tag TAG
OK
127.0.0.1:6379>
127.0.0.1:6379> FT.CREATE idx11 SCHEMA vec VECTOR HNSW 6 TYPE FLOAT32 DIM 4 DISTANCE_METRIC L2 tag TAG
(error) Invalid range: Value above maximum; Maximum number of indexes reached (10). Cannot create additional indexes.
127.0.0.1:6379>
127.0.0.1:6379> CONFIG set search.max-indexes 20
(error) ERR CONFIG SET failed (possibly related to argument 'search.max-indexes') - argument must be between 1 and 10 inclusive
127.0.0.1:6379> CONFIG get search.max-indexes
1) "search.max-indexes"
2) "10"
127.0.0.1:6379>

I have changed max limit to UINT32_MAX as it was declared and also updated the CHECK_RANGE maco to handle larger values as well, also updated the config get return value not cast to int to be consistent.

after the changes the results.

127.0.0.1:6379>
127.0.0.1:6379> CONFIG get search.max-indexes
1) "search.max-indexes"
2) "10"
127.0.0.1:6379>
127.0.0.1:6379>
127.0.0.1:6379> CONFIG set search.max-indexes 4294967292
OK
127.0.0.1:6379>
127.0.0.1:6379> CONFIG get search.max-indexes
1) "search.max-indexes"
2) "4294967292"
127.0.0.1:6379>
127.0.0.1:6379>
127.0.0.1:6379> CONFIG set search.max-indexes 4294967300
(error) ERR CONFIG SET failed (possibly related to argument 'search.max-indexes') - argument must be between 1 and 4294967295 inclusive