* chore(weed/wdclient): prune unused functions
* chore(weed/wdclient): prune test-only functions and associated tests
* chore(weed/wdclient): remove dead cursor field
The cursor field and its initialization are no longer used after
the removal of getLocationIndex.
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Co-authored-by: Chris Lu <chris.lu@gmail.com>
The vidMap structure is modified to a linked list structure (the length is limited to 5). When the vidMap is reset, the current vidMap is added to the new vidMap as a cache node. When the query locations is empty, the cache node is searched to avoid problems when the master switches leaders.