feat: create `canary` npm tag and stabilize weekly releases

[weboko]

Description

We need clear separation between npm tags js-waku uses.

Presently we have:

• next for ad-hoc releases;
• latest for monthly stable release;

Proposed new strategy:

• ad-hoc releases done for dogfooding under canary;
• weekly releases that are done under next;
• monthly releases under latest;

To match new way of releases we need:

• change existing job for next release to be done on a weekly basis;
• change existing ad-hoc releases to be done under canary tag;

[fryorcraken]

At the end of the day, the reason to release often and early is to encourage dogfooding by "users", that we want to see as "co-developers".

In terms of weekly releasing, the point is to also communicate about those releases so developers can try them out.

Hence, it does not have to fit a strictly weekly release, especially if a release is empty.

It can be more about:

• if a developer merge a PR with some cool feature, then they can kick off a next release and talk about it
• if it's been 10 days since last next release because nobody kick off, but there is a number of small fixes in it, then do a new next release
• find to have a latest stable release if you really prefer.

What matters most is that every CC should want to push the work they have done to get it used by other. So it should not just be about "I did the PR I was told to do" but more "I did some cool feature and I want to push it so that people use it".