feat: Add group_users mode

[gtema]

• add view for managing group users
• sketch commands that would be available in individual identity modes

[gtema]

@markus-hentsch with this PR merged you can better debug your backspace/del issue by running RUST_LOG=debug cargo r --bin ostui, pressing backspace/del (maybe few times) and then looking into ~/.local/share/openstack_tui/openstack_tui.log where you should see entries like:

2024-11-15T13:18:06.318268Z DEBUG handle_key_event{key=KeyEvent { code: Backspace, modifiers: KeyModifiers(0x0), kind: Press, state: KeyEventState(0x0) }}: openstack_tui/src/app.rs:235: Key event received
2024-11-15T13:18:06.457967Z DEBUG handle_key_event{key=KeyEvent { code: Backspace, modifiers: KeyModifiers(0x0), kind: Press, state: KeyEventState(0x0) }}: openstack_tui/src/app.rs:235: Key event received
2024-11-15T13:18:06.598215Z DEBUG handle_key_event{key=KeyEvent { code: Backspace, modifiers: KeyModifiers(0x0), kind: Press, state: KeyEventState(0x0) }}: openstack_tui/src/app.rs:235: Key event received
2024-11-15T13:18:06.933357Z DEBUG handle_key_event{key=KeyEvent { code: Delete, modifiers: KeyModifiers(0x0), kind: Press, state: KeyEventState(0x0) }}: openstack_tui/src/app.rs:235: Key event received
2024-11-15T13:18:07.068271Z DEBUG handle_key_event{key=KeyEvent { code: Delete, modifiers: KeyModifiers(0x0), kind: Press, state: KeyEventState(0x0) }}: openstack_tui/src/app.rs:235: Key event received
2024-11-15T13:18:07.223013Z DEBUG handle_key_event{key=KeyEvent { code: Delete, modifiers: KeyModifiers(0x0), kind: Press, state: KeyEventState(0x0) }}: openstack_tui/src/app.rs:235: Key event received

If you do not have proper event for "Backspace" please let me know

[markus-hentsch]

@markus-hentsch with this PR merged you can better debug your backspace/del issue by running RUST_LOG=debug cargo r --bin ostui, pressing backspace/del (maybe few times) and then looking into ~/.local/share/openstack_tui/openstack_tui.log where you should see entries like:

2024-11-15T13:18:06.318268Z DEBUG handle_key_event{key=KeyEvent { code: Backspace, modifiers: KeyModifiers(0x0), kind: Press, state: KeyEventState(0x0) }}: openstack_tui/src/app.rs:235: Key event received
2024-11-15T13:18:06.457967Z DEBUG handle_key_event{key=KeyEvent { code: Backspace, modifiers: KeyModifiers(0x0), kind: Press, state: KeyEventState(0x0) }}: openstack_tui/src/app.rs:235: Key event received
2024-11-15T13:18:06.598215Z DEBUG handle_key_event{key=KeyEvent { code: Backspace, modifiers: KeyModifiers(0x0), kind: Press, state: KeyEventState(0x0) }}: openstack_tui/src/app.rs:235: Key event received
2024-11-15T13:18:06.933357Z DEBUG handle_key_event{key=KeyEvent { code: Delete, modifiers: KeyModifiers(0x0), kind: Press, state: KeyEventState(0x0) }}: openstack_tui/src/app.rs:235: Key event received
2024-11-15T13:18:07.068271Z DEBUG handle_key_event{key=KeyEvent { code: Delete, modifiers: KeyModifiers(0x0), kind: Press, state: KeyEventState(0x0) }}: openstack_tui/src/app.rs:235: Key event received
2024-11-15T13:18:07.223013Z DEBUG handle_key_event{key=KeyEvent { code: Delete, modifiers: KeyModifiers(0x0), kind: Press, state: KeyEventState(0x0) }}: openstack_tui/src/app.rs:235: Key event received

If you do not have proper event for "Backspace" please let me know

I now tried QTerminal and Konsole, both Qt-based terminal emulators. The problem only happens in QTerminal but not in Konsole. Turns out that leaving QTerminal's behavior > emulation setting at "default" causes the issue but changing it to "linux" fixes the behavior for QTerminal. The setting "vt420pc" shows the same broken behavior so I assume it is what it defaults to.

Pressing Backspace in Konsole or QTerminal with behavior > emulation set to "linux":

2024-11-18T16:34:21.877812Z DEBUG handle_key_event{key=KeyEvent { code: Backspace, modifiers: KeyModifiers(0x0), kind: Press, state: KeyEventState(0x0) }}: openstack_tui/src/app.rs:249: Key event received

Pressing Backspace in QTerminal (with behavior > emulation set to "default" or "vt420pc"):

2024-11-18T16:35:12.257747Z DEBUG handle_key_event{key=KeyEvent { code: Char('h'), modifiers: KeyModifiers(CONTROL), kind: Press, state: KeyEventState(0x0) }}: openstack_tui/src/app.rs:249: Key event received

A bit of research made me realize that ctrl+h is the historical implementation of the Backspace behavior:

The key labeled "backspace" is a matter of contention. Technically, it ought to send ^H simply because that is the name of the ASCII control character. Others differ, because their expectations have been affected by the history of this feature [...]

(source)

Seems like all TUI interfaces that I used so far are simply compatible with this historical way of treating Backspace.
Your call if you want to implement support for this old-fashioned behavior :)