[internal][deps][suggestion]: some future release - updating obsidian API (and minAppVersion?)

[AnnaKornfeldSimpson]

Followup from discussion with @claremacrae about out-of-date dependency moment used by the obsidian API. This post is just to collect a bunch of information so we can reference it in the future, I am not suggesting any action right now.
Context:
merged PR #854, merged dependabot PR #862
#872 (comment)
#872 (comment)

• Obsidian stable got bumped to 0.15.6! We no longer have to worry about smoke testing on old 0.14 versions of Obsidian.

• The Obsidian API GitHub repo has updated its dependency on moment to get rid of the security warning, but not released a new version with that patch to npm yet (current obsidian@latest via npm is API version 0.15.4 which is still using the old moment). I think the most reasonable thing to do is to wait for the npm update.

• Once there is a obsidian 0.15.5 on npm, I think it might be reasonable to update our obsidian API dependency (the only outdated dependency not updated in chore: deps-dev upgrades, see full list in Description #872 or any recent dependabot PRs) to 0.15.5. This requires also adding @codemirror/state as some kind of dependency (dev or peer?) since it is a peer dependency of obsidian, but otherwise code builds and passes all automated tests without any further changes. I did not do a smoke test.

• Updating the obsidian api might require also increasing the minAppVersion in manifest.json - from searching and reading I have been unable to tell whether that is required in all cases or just some - but that is hopefully fine because stable now has an 0.15 option. (What about mobile? The versioning numbers there seem totally different, so I do not know how minAppVersion is interpreted on mobile.)

• There was a post on the Obsidian Forum today from the developers about ensuring plugin compatibility with the new pop-out windows. Any changes needed to address this may require an update to the obsidian API to 0.15.x (and therefore a minAppVersion update as well), but I could not tell from a brief search if any of the code in tasks needed changing. In general, I think we want the default behavior (e.g. all calls to window.moment refer to the moment instance in the main window), except for things directly related to placing HTMLElements in the correct spot.

• In short, if we get an issue about the new pop-out-windows behavior, we will probably have to update the obsidian api dependency to 0.15.5 and the minAppVersion in manifest.json to 0.15. Otherwise, we will soon (but not quite yet) be able to get rid of the security warning around the outdated moment dependency by upgrading the obsidian api dependency, which is great!