ci: fixed stale pr workflow

[goniz]

The stale PR workflow didn’t actually worked since the stale check used last_updated field which didn’t reflect the actual last activity.

The ‘dev’ branch is frequently forced pushed and it registers as activity on the PRs that target it. (Base branch is considered updated).

This PR changes the logic of the stale PR check to use:

• Last commit date
• Last comment date
• PR creation date

[github-actions]

Hey! Your PR title ci: fixed stale pr workflow doesn't follow conventional commit format.

Please update it to start with one of:

• feat: or feat(scope): new feature
• fix: or fix(scope): bug fix
• docs: or docs(scope): documentation changes
• chore: or chore(scope): maintenance tasks
• refactor: or refactor(scope): code refactoring
• test: or test(scope): adding or updating tests

Where scope is the package name (e.g., app, desktop, opencode).

See CONTRIBUTING.md for details.

[github-actions]

The following comment was made by an LLM, it may be inaccurate:

No duplicate PRs found

[rekram1-node]

/review

[github-actions]

lgtm