Use `DAV:owner` for "Show only personal"

[rfc2822]

Depends on #1588

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Check whether "Show only personal" can use DAV:owner instead of "belongs to a homeset that belongs to the user".

Check especially with eGroupware. We had found the current solution with the homesets when we tested DAVx5 with eGroupware admin accounts, which would have many entries without such an option.

However at that time DAVx⁵ didn't query the DAV:owner, and now it does.

[ArnyminerZ]

So we'd be changing this, right?

davx5-ose/app/src/main/kotlin/at/bitfire/davdroid/servicedetection/CollectionListRefresher.kt

Lines 172 to 176 in ba7f95a

	// HomeSet is considered personal if this is the outer recursion call,
	// This is because we assume the first call to query the current-user-principal
	// Note: This is not be be confused with the DAV:owner attribute. Home sets can be owned by
	// other principals while still being considered "personal" (belonging to the current-user-principal)
	// and an owned home set need not always be personal either.

[rfc2822]

Yes, we have to try with eGroupware and see whether we can replace the complicated current

personal = in some home-set with layer 1

logic by a simple

personal = DAV:owner is current-user-principal.

[sunkup]

So eGroupware has given green light?

[rfc2822]

So eGroupware has given green light?

They don't need to do so. We can test with eGroupware (admin account), and if the Show only personal reduces the huge amount of collections to those of the admin account, its fine.