/context add should support URLs such as Quip or wiki, with a periodic sync to stay up-to-date, and on /compact

### Checks

- [x] I have searched [github.com/aws/amazon-q-developer-cli/issues](https://github.com/aws/amazon-q-developer-cli/issues?q=) and there are no duplicates of my issue

### Operating system

macOS 15.4.1 (24E263)

### Expected behaviour

See Title. While context management feature works well with static markdown files, being able to pull additional, up-to-date information from web-based documentation is always helpful. MCP tooling can access these, but it's not connected to the /context feature. Other tools at Amazon are able to do this already, so this is more about asking for parity in Q CLI.

### Actual behaviour

/context add rejects URLs, especially Quip URLs

### Steps to reproduce

1. try to /context add a quip URL
2. when it doesn't work, translate the quip to a static markdown file to add as context
3. realize that the static markdown file will be out-of-sync with the quip whenever it updates, unless the translation step is re-executed.