Zoekt matches on the same line count as one result

Background

Found when working on !178232 (merged)

The Zoekt API returns matchCount which is the count of matches returned. However, what this really means is count of line matches (not matches total). If a line contains multiple matches, it only counts 1 time.

The Zoekt multi-match UI highlights each match (not each line). When there are only a few results, there is an obvious discrepancy between result count and number of matches highlighted.

Proposal

Document the issue in the exact code search user docs under known issues

We should decide if this should be fixed or not. Some items to note:

• Advanced search has the same behavior
• Zoekt UI (web server) has the same behavior