[Feature]: generate quantity - Generates the number of commit messages to choose from

Description

Hello,
In my usage scenario, the content generated by AI is often not what I want to use, and it usually takes multiple attempts to get what I want to use.
I hope to generate multiple commit titles for me to choose from. For the simplicity of the screen, I think oco can not generate a commit body when starting this function.

Suggested Solution

Current：Confirm the commit message?

chore(tests.mak): add Makefile targets for building

- Introduced Makefile targets for building and cleaning project files
- Simplified the build workflow, reducing setup time for development
- Adjusted dependencies to ensure compatibility with the new targets
 

When the setting is completed： oco config set generate=5
Expect：Pick a commit message to use

chore(docs): update README with new installation steps
chore(scripts): add Makefile targets for testing
chore(build): optimize Dockerfile for faster builds
chore(deps): upgrade dependencies for improved security
chore(ci): add new workflow for automated testing

Alternatives

No response

Additional Context

No response

Start by tracing the oco config set generate=5 setting into the current commit-message confirmation flow. Check how generated titles and bodies are presented, then determine how the configured number of alternatives should be displayed for selection. Done means users can choose one of the generated commit titles and the initial multi-option flow does not generate a commit body.