Using doxygengroup in multiple locations to summarize certain functions

I have a not-so-small code base, and in the documentation I have a separate section which highlights certain functions and provides additional explanation on how to use them (let's call it "common tasks"). These functions are documented as part of their own namespace or class, while the common tasks documentation is a separate page.

In order to recall at least the function signature in common tasks page, I added the functions to a Doxygen group, and I had planned to issue the doxygengroup directive there, with the no-link option. In a minimal example:

Unique source file:

/**
 * @defgroup bars Bar functions
 */

/**
 * Some functions, some are in a group.
 */
namespace foo {
    /**
     * A type for a parameter.
     */
    struct parm {};

    /**
     * @brief Acts on the first bar.
     * @ingroup bars
     */
    void bar1(parm);

    /**
     * @brief Acts on the second bar.
     * @ingroup bars
     */
    void bar2(parm);

    /**
     * @brief Baz.
     */
    void baz();
}

Relevant RST content:

.. doxygennamespace:: foo
   :project: Test

.. doxygengroup:: bars
   :project: Test
   :no-link:

However this is not working very well:

The namespace is lost: the parm type does not link to the original type.
If I need to include the same group in different places on the same page (this happens in the real projects, some functions are involved in multiple common tasks), even with the no-link option, I get a WARNING: Duplicate C++ declaration

I tried using outline too but it did not help. Is there any way to work around these without having to list manually all the functions and their signature?

Ideally, what I would love to have would be

the function names link to the corresponding anchor, and they are complete of namespace, as if I had referred to them as
```
:func:`foo::bar1`
```
it would be possible to select a certain level of detail, such as "brief", "detailed", "full" to display only brief description, the full description with notes and so on, or the full function documentation including parameters. Perhaps a :summarize: brief|detailed|full option to doxygengroup?
it would be possible to use this in several places without generating warnings.

breathe-doc / breathe

Using doxygengroup in multiple locations to summarize certain functions #893