vuke analyze takes a single --key argument. When investigating a cluster of potentially related keys (common in puzzle solving or incident response), you have to run the command separately for each one.

Supporting multiple keys would make batch analysis practical:

# multiple --key flags
vuke analyze --key 0x1a2b --key 0x3c4d --analyzer milksad

# or from a file
vuke analyze --key-file suspicious_keys.txt --analyzer lcg

Each key would run through the selected analyzers independently. The output (both human-readable and --json) would group results per key.

The --key-file variant would read one key per line (same formats parse_private_key already handles: hex, WIF, decimal). This pairs well with piping output from other tools or extracting keys from transaction data.

The existing run_analyze function already loops over analyzers for a single key. The change is mostly lifting that into an outer loop over keys, plus adjusting the output formatting to handle multiple key sections.