## ADDED Requirements
### Requirement: Summary note includes a one-line blurb
The `write_summary` tool SHALL require a one-line summary parameter in addition to the markdown summary body.

Meeting Assistant SHALL reject `write_summary` calls when the one-line summary contains line breaks.

Meeting Assistant SHALL write the one-line summary into summary note frontmatter as `oneliner`.

The summary-agent instructions SHALL tell the agent to keep the one-line summary very short, blurb-like, and concise, with complete sentences not required.

#### Scenario: Summary one-liner is written to frontmatter
- **WHEN** the summary agent calls `write_summary` with markdown content and one-line summary `Architecture risks and next steps`
- **THEN** Meeting Assistant writes `oneliner: Architecture risks and next steps` to the summary note frontmatter

#### Scenario: Multiline one-liner is rejected
- **WHEN** the summary agent calls `write_summary` with a one-line summary containing a line break
- **THEN** Meeting Assistant refuses the write
- **AND** does not mark the summary as written