My solution is to keep journals / diaries per project. In my experience, journals can handle even the most extreme interruptions (long travels abroad, urgent switches to different projects, long stretches of manager's schedule, health emergencies, etc).
I keep my journals in Workflowy, organized as follows: root folders for projects, subfolders for years, sub-subfolders for months, and the records at the bottom level.
It's not necessary to write daily. Write only if you have a message to your "future you" that could help him / her pick up the project after an interruption. Describe open problems, dilemmas you're facing, dead-ends you've encountered, decisions you've made, and next actions.
It's not necessary to write proper prose. Writing in caveman language is perfectly fine, as long as the future you can understand that.