Bugfix: add ability for view only users to interact with preview page and view data in inspector

[t-heuser]

This is the successor of #3921. It contains the bugfix and implements all remarks from the comments of the original PR.

What I did
Previous Behaviour:

• When a view-only user clicks on a node on the preview page nothing happens.
• The user can only select nodes via the content tree (left sidebar)
• The user can not see any node data in the inspector (right sidebar)

Fixed Behaviour:

• The user can interact with nodes on the preview page (highlighting is visible)
• The user can view - but not edit - node data in the inspector (right sidebar)

How I did it

• Backend: gate rendering on read permission instead of edit permission — added a canReadProperties check (based on ReadNodePrivilege) to NodePolicyService, exposed it in the node policy data, and switched AugmentationAspect to use it so content metadata is still rendered for view-only users.
• Frontend: don't boot inline editors for content the user can't edit — initializePropertyDomNode.js skips editor initialization when the workspace is read-only or the (lazy-loaded, awaited via store subscription) node policy disallows editing, replacing the old approach of blocking the whole guest frame / read-only CKEditor instances, so view-only users can interact with the preview page normally.
• Inspector: show node data read-only — tab/property visibility now checks canReadProperties instead of canEdit, and InspectorEditorEnvelope disables editors when the node policy has canEdit: false, letting view-only users see values without editing them.

How to verify it

• Create a role (e.g. with the Sandstorm.NeosAcl package) that has permission to view but not to edit/create.
• When browsing content the user should be able to click on nodes in the preview page and see their data in the inspector.

BEFORE

AFTER

[mhsdesign]

Hi thanks ill need to find some time to retest this. It seems everything is in one commit so i cannot judge by reading whats new ... but maybe thats not a problem:)

[t-heuser]

@mhsdesign Almost everything in the JS files changed, the PHP part stayed the same :)

[t-heuser]

@mhsdesign Any updates? :)

[mhsdesign]

Nope im still occupied with the 9.2 release. But i wonder, the original pr from robert did not look that bad and i did understood it last time i reviewed ^^ i dont understand the transition from his javascript code changes to this fully new approach - im missing that diff^^ - why this is the successor. Here are also some oddities we have never used before like store.subscribe() so thats definitely a sign that something is not really right here.