Establish and Document Rules for Commit Messages and Pull Requests

[tdog191]

To ensure that reviewers can understand commit messages and pull requests quickly, guidelines on their formats and content should be established and documented accordingly.

For commit messages, How to Write a Git Commit Message is a blog post that discusses what I consider good guidelines for commit messages:

1. Separate subject from body with a blank line
2. Limit the subject line to 50 characters
3. Capitalize the subject line
4. Do not end the subject line with a period
5. Use the imperative mood in the subject line
6. Wrap the body at 72 characters
7. Use the body to explain what and why vs. how

Additionally, the blog post also provides an example of a commit message that lists resolved and related issue numbers at the bottom:

Resolves: #123
See also: #456, #789

Commit 042edf7 is an example of what I would consider an ideal commit message format.

For pull requests, it is important to provide a big-picture overview of what the pull request is doing in the first comment. For pull requests related to the frontend, it is also valuable to provide screenshots of new or updated UI. The first comment of #45 is what I would consider an ideal example of both of these principles.