## ADDED Requirements

### Requirement: Can read package lists from stdin

The system SHALL accept package names from standard input, where each line represents a package name.

#### Scenario: Packages from stdin are read correctly
- **WHEN** package names are passed via stdin separated by whitespace, tabs, or newlines
- **THEN** system shall parse each unique package name from the input stream

#### Scenario: Empty stdin input is handled
- **WHEN** stdin contains no package names
- **THEN** system shall skip stdin input processing

#### Scenario: Whitespace normalization
- **WHEN** packages are separated by multiple spaces, tabs, or newlines
- **THEN** each package name shall have leading/trailing whitespace trimmed