[Qt6] When layers are in edit mode, Dataset and Basket Managers should be read only

[gacarrillor]

When changing the Dataset of a specific basket in the Basket Manager (Layers were in Edit model), we've got an error message:

I guess the message is expected, but then we could disable the edit buttons in Dataset and Basket Managers if layers are on edit mode.

I attempted the same edit operation with layers in non-edit mode, and then it worked!

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Tests done using the Qt6-enabled dev version at #1036 (comment) on Windows (Qt6-build).

I've been unable to reproduce using a Qt5 build on GNU/Linux.

[signedav]

Even without receiving a lock it would make sense to disable edit mode (like e.g. the validator does it)

[gacarrillor]

For the record, on a QGIS Qt5-build, the basket can actually be edited, as the Dataset Manager seems to force a commit on the pending edits before opening.

[signedav]

Ah, it does it, but this does not work with Qt6.

Hm... 🤔

[gacarrillor]

Ah, it does it, but this does not work with Qt6.

Hm... 🤔

Not in my test, perhaps the attempt to commit somehow failed or something.