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[IMP] documents, *: modernize access rights, sharing, and actions

#### Model changes
* `documents.folder` is merged into `documents.document` ("`document`" below)
    => Records with `type=folder`
* `documents.share` is removed,
    => Sharing is now defined on each `documents.document` (see below)
* `documents.access` is added to store partners access and access logs
* `documents.workflow.action` is removed and functionally replaced by
    `ir.embedded.actions` records linked to `ir.actions.server`
* `documents.facet` are removed, `documents.tag` are now available cross-app

##### `document` types

Functionally, folders are now displayed together with files in our kanban view,
where folders can be entered with double click.
Shortcuts are also introduced for quick access to a `document` from
another place.

Technically, types are materialized in the `type`, `attachment_id`, and
`shortcut_document_id` fields.
The type can be `binary`, `url`, `folder`.
The old `request` type is virtualized by the `type=binary` with
`attachment_id=False` condition (which was already true),
and shortcuts have a set `shortcut_document_id` and match their type.

##### Access rights
Access rights and sharing are now directly, and only, defined on each
`document` and result in a user's permission `user_permission`.
  * User permissions are:
    * `view`: right to view a document's fields value.
    * `edit`: right to edit a document + upload inside for folders, update sharing
      Note that public users are only able to upload.
    * `none`: no right
  * These permissions can be defined to give access to users via a combination
    of parameters. When users match multiple conditions, they are granted the
    highest permission given by these:
    * The `owner` of a document now has `edit` permission.
    * Individual partners can be added (see Knowledge's "Members")
      (m2m `documents.access`)
    * All internal users via `access_internal`
    * All users that have the link to the document (enabled via `access_via_link`)
       That is either:
       * Having the URL (access token)
       * Unless marked as "non-discoverable" via `is_access_via_link_hidden`
         having access to a related record:
          * The parent folder,
          * A shortcut to the document,
          * In selected cases (such as project), access to the related record
      This access is logged so that on new access to the app, a visited
      document is still accessible (as long as it is shared in the same way)
      without having to click on the direct link or related record again.
  * Upon creating a document inside a folder:
    * Default: Access rights on the document are inherited from the folder.
    * Customization: Via the documents.mixin, other values can be defined
      depending on the linked record.

* Documents will now appear in different sections:
  * Company: All documents owned by OdooBot and their children,
     as well as all documents shared with all internal users
  * My drive: Personal space for each internal user
  * Shared with me: All documents shared with the user that are
    not in the Company drive

* Shortcuts can be created to create quick references to documents in other
places without the need to duplicate the document or spread access rights
management.

[...]

task-4014624

Co-authored-by: std-odoo <std@odoo.com>
Co-authored-by: Pierre-Yves Dufays <pydu@odoo.com>
Co-authored-by: Julien Castiaux <juc@odoo.com>
Co-authored-by: Lopes Marc (loma) <loma@odoo.com>
Co-authored-by: Patrick Hoste <pko@odoo.com>