Find credit unions by name, state, charter type (federal/state) or asset peer group, in a given quarter (default: latest). Name matching ignores case, punctuation and the words 'federal credit union' / 'FCU', so 'SRP Federal Credit Union' finds 'SRP'; partial names work. It also matches former names (a credit union that was renamed shows up under the old name, match = former_name, with its current name) and a few brand names (BECU, PenFed, SECU). Results are ranked: match = exact, starts_with, contains, former_name, then larger assets first. Each row has 'ambiguous': true when several different credit unions fit the name. In that case ask the user which one they mean (use city and state to tell them apart) rather than picking the first. If nothing matches, the result is one row with 'no_match' explaining why (for example the credit union merged or closed, with its last reported quarter). Returns cu_number, name, location, total assets, members. Use the returned cu_number in the other tools. Only federally insured credit unions.