Extension:CheckUser/cu useragent clienthints table

A table for the extension used to store unique combinations of client hints header names and their values. The rows in this table are referenced by the many-to-many map table.

uach_id
Primary key, used to uniquely identify a cu_useragent_clienthints row. Referenced by the table in the uachm_uach_id column.

uach_name
The name of the client hint value. The combinations of uach_name and uach_value are unique.

uach_value
The value associated with the name in uach_name. The combinations of uach_name and uach_value are unique.

Schema
mysql> describe cu_useragent_clienthints; ++--+--+-+-++ ++--+--+-+-++ ++--+--+-+-++
 * Field     | Type             | Null | Key | Default | Extra          |
 * uach_id   | int(10) unsigned | NO   | PRI | NULL    | auto_increment |
 * uach_name | varbinary(32)    | NO   | MUL | NULL    |                |
 * uach_value | varbinary(255)  | NO   |     | NULL    |                |

Indexes
 mysql> show index in cu_useragent_clienthints; +--++-+--+-+---+-+--++--++-+---+ +--++-+--+-+---+-+--++--++-+---+ +--++-+--+-+---+-+--++--++-+---+
 * Table                   | Non_unique | Key_name        | Seq_in_index | Column_name | Collation | Cardinality | Sub_part | Packed | Null | Index_type | Comment | Index_comment |
 * cu_useragent_clienthints |         0 | PRIMARY         |            1 | uach_id     | A         |           0 |     NULL | NULL   |      | BTREE      |         |               |
 * cu_useragent_clienthints |         0 | uach_name_value |            1 | uach_name   | A         |           0 |     NULL | NULL   |      | BTREE      |         |               |
 * cu_useragent_clienthints |         0 | uach_name_value |            2 | uach_value  | A         |           0 |     NULL | NULL   |      | BTREE      |         |               |