chore: auto-commit (57 archivos)

- frontend/functions/core/format_datetime_short.md
- frontend/functions/core/format_datetime_short.test.ts
- frontend/functions/core/format_datetime_short.ts
- frontend/functions/core/format_duration.md
- frontend/functions/core/format_duration.test.ts
- frontend/functions/core/format_duration.ts
- frontend/functions/core/month_grid.md
- frontend/functions/core/month_grid.test.ts
- frontend/functions/core/month_grid.ts
- frontend/functions/core/string_hash_palette.md
- ...

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

functions/infra/sqlite_column_exists.go

@@ -0,0 +1,30 @@
+package infra
+
+import (
+	"database/sql"
+	"fmt"
+)
+
+// ColumnExists reports whether the named column exists in the given table
+// by querying PRAGMA table_info. Returns false if the table does not exist.
+func ColumnExists(conn *sql.DB, table, name string) (bool, error) {
+	rows, err := conn.Query(fmt.Sprintf("PRAGMA table_info(%s)", table))
+	if err != nil {
+		return false, err
+	}
+	defer rows.Close()
+	for rows.Next() {
+		var cid int
+		var colName, ctype string
+		var notnull int
+		var dflt sql.NullString
+		var pk int
+		if err := rows.Scan(&cid, &colName, &ctype, &notnull, &dflt, &pk); err != nil {
+			return false, err
+		}
+		if colName == name {
+			return true, nil
+		}
+	}
+	return false, rows.Err()
+}