update(group-matching): use startswith for group matching (cross-seed…

…#580)

a few trackers truncate release names after certain lengths, leaving the
possibility (although needs to be the right length) for groups to be
truncated and partial groupnames returned from Torznab.

While the truncation will not always be mid-groupname - this will
provide a marginal amount of matches that otherwise would not be
snatched.

Potentially could use a "blacklist" for producing no-match when group
name evaluates to something like "-DL" or something, to catch WEB-DL
when truncated prior to the group name start, however this is a bit iffy
too.

src/decide.ts

@@ -119,8 +119,9 @@ function releaseGroupDoesMatch(
 	if (!searcheeMatch || !candidateMatch) {
 		return matchMode === MatchMode.RISKY;
 	}
-
-	return searcheeMatch[0].toLowerCase() === candidateMatch[0].toLowerCase();
+	return searcheeMatch[0]
+		.toLowerCase()
+		.startsWith(candidateMatch[0].toLowerCase());
 }
 
 async function assessCandidateHelper(