Enforce multiline rule for single multiline arguments

Update go-style guide and cursor rule to clarify that even a single
argument spanning multiple lines must break after the opening
parenthesis. Fix six violations across the branch.

Signed-off-by: Émile Ré <emile@probo.com>

contrib/claude/go-style.md

@@ -106,6 +106,33 @@ t.Run(
 svc, err := foo.NewService(ctx, db, logger, foo.Config{
 	Interval: 10 * time.Second,
 })
+
+// Bad — single multiline argument starts on the opening ( line
+body, err := json.Marshal(firecrawlRequest{
+	Query: query,
+	Limit: maxResults,
+})
+
+// Good — single multiline argument: break after (, trailing comma, ) alone
+body, err := json.Marshal(
+	firecrawlRequest{
+		Query: query,
+		Limit: maxResults,
+	},
+)
+
+// Bad — function literal starts on the opening ( line
+sort.Slice(items, func(i, j int) bool {
+	return items[i].Name < items[j].Name
+})
+
+// Good — function literal on its own line
+sort.Slice(
+	items,
+	func(i, j int) bool {
+		return items[i].Name < items[j].Name
+	},
+)
 ```
 
 The same rule applies to **method calls** `x.M(a1, …)` — the receiver is already bound; the rule applies to the **argument list** after the method name.

pkg/agent/tools/search/firecrawl.go

@@ -91,10 +91,12 @@ func firecrawlSearch(
 		return nil, fmt.Errorf("cannot build search URL: %w", err)
 	}
 
-	body, err := json.Marshal(firecrawlRequest{
-		Query: query,
-		Limit: maxResults,
-	})
+	body, err := json.Marshal(
+		firecrawlRequest{
+			Query: query,
+			Limit: maxResults,
+		},
+	)
 	if err != nil {
 		return nil, fmt.Errorf("cannot marshal request: %w", err)
 	}
@@ -132,11 +134,14 @@ func firecrawlSearch(
 
 	results := make([]searchResult, 0, len(fcResp.Data.Web))
 	for _, r := range fcResp.Data.Web {
-		results = append(results, searchResult{
-			Title:   r.Title,
-			URL:     r.URL,
-			Snippet: r.Description,
-		})
+		results = append(
+			results,
+			searchResult{
+				Title:   r.Title,
+				URL:     r.URL,
+				Snippet: r.Description,
+			},
+		)
 	}
 
 	return results, nil

pkg/cookiebanner/pattern_analysis_worker.go

@@ -306,18 +306,21 @@ func findMergeGroups(
 	// Sort: heuristic first, then descending specificity (more fixed
 	// characters), then descending coverage, then template name for a
 	// fully deterministic order.
-	sort.Slice(candidates, func(i, j int) bool {
-		if candidates[i].isHeuristic != candidates[j].isHeuristic {
-			return candidates[i].isHeuristic
-		}
-		if candidates[i].fixedChars != candidates[j].fixedChars {
-			return candidates[i].fixedChars > candidates[j].fixedChars
-		}
-		if len(candidates[i].patterns) != len(candidates[j].patterns) {
-			return len(candidates[i].patterns) > len(candidates[j].patterns)
-		}
-		return candidates[i].key.template < candidates[j].key.template
-	})
+	sort.Slice(
+		candidates,
+		func(i, j int) bool {
+			if candidates[i].isHeuristic != candidates[j].isHeuristic {
+				return candidates[i].isHeuristic
+			}
+			if candidates[i].fixedChars != candidates[j].fixedChars {
+				return candidates[i].fixedChars > candidates[j].fixedChars
+			}
+			if len(candidates[i].patterns) != len(candidates[j].patterns) {
+				return len(candidates[i].patterns) > len(candidates[j].patterns)
+			}
+			return candidates[i].key.template < candidates[j].key.template
+		},
+	)
 
 	assigned := make(map[*coredata.TrackerPattern]bool)
 	groups := make(map[mergeGroupKey][]*coredata.TrackerPattern)
@@ -598,9 +601,12 @@ func (h *patternAnalysisHandler) adoptUncategorisedPatterns(
 		return false, nil
 	}
 
-	sort.Slice(globPatterns, func(i, j int) bool {
-		return len(globPatterns[i].Pattern) > len(globPatterns[j].Pattern)
-	})
+	sort.Slice(
+		globPatterns,
+		func(i, j int) bool {
+			return len(globPatterns[i].Pattern) > len(globPatterns[j].Pattern)
+		},
+	)
 
 	exactMatchType := coredata.TrackerPatternMatchTypeExact
 	var uncategorisedExact coredata.TrackerPatterns

pkg/coredata/common_tracker_pattern.go

@@ -251,10 +251,13 @@ RETURNING id, (xmax = 0) AS inserted
 		Inserted bool
 	}
 
-	res, err := pgx.CollectExactlyOneRow(rows, func(row pgx.CollectableRow) (upsertResult, error) {
-		var r upsertResult
-		return r, row.Scan(&r.ID, &r.Inserted)
-	})
+	res, err := pgx.CollectExactlyOneRow(
+		rows,
+		func(row pgx.CollectableRow) (upsertResult, error) {
+			var r upsertResult
+			return r, row.Scan(&r.ID, &r.Inserted)
+		},
+	)
 	if err != nil {
 		return gid.GID{}, false, fmt.Errorf("cannot collect upsert result: %w", err)
 	}

pkg/proboctl/seed/common-tracker-patterns/common_tracker_patterns.go

@@ -344,12 +344,15 @@ var domainValidRe = regexp.MustCompile(`^[a-zA-Z0-9][a-zA-Z0-9.-]*[a-zA-Z]$`)
 func normalizeDomain(s string) string {
 	s = strings.TrimSpace(s)
 
-	s = strings.Map(func(r rune) rune {
-		if r == '\u200b' || r == '\ufeff' {
-			return -1
-		}
-		return r
-	}, s)
+	s = strings.Map(
+		func(r rune) rune {
+			if r == '\u200b' || r == '\ufeff' {
+				return -1
+			}
+			return r
+		},
+		s,
+	)
 
 	if idx := strings.Index(s, " or "); idx != -1 {
 		s = s[:idx]