Fix COPY FROM STDIN regex to handle transpiled SQL

The transpiler removes the space between table name and column list:
- Before: COPY "table" ("col") FROM STDIN
- After:  COPY table(col) FROM STDIN

Updated regex to use \s* (optional space) instead of \s+ (required space)
so it matches both formats.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <[email protected]>

Author: EDsCODE

server/conn.go

@@ -608,7 +608,7 @@ func (c *clientConn) buildCommandTag(cmdType string, result sql.Result) string {
 // Regular expressions for parsing COPY commands
 var (
 	copyToStdoutRegex   = regexp.MustCompile(`(?i)COPY\s+(.+?)\s+TO\s+STDOUT`)
-	copyFromStdinRegex  = regexp.MustCompile(`(?i)COPY\s+(\S+)\s+(?:\(([^)]+)\)\s+)?FROM\s+STDIN`)
+	copyFromStdinRegex  = regexp.MustCompile(`(?i)COPY\s+(\S+)\s*(?:\(([^)]+)\)\s*)?FROM\s+STDIN`)
 	copyWithCSVRegex    = regexp.MustCompile(`(?i)\bCSV\b`)
 	copyWithHeaderRegex = regexp.MustCompile(`(?i)\bHEADER\b`)
 	copyDelimiterRegex  = regexp.MustCompile(`(?i)\bDELIMITER\s+['"](.)['"]\b`)