Incomplete budget voting message does not display the pending budget name #17475

Describe the bug

When voting on a budget, if the voting process is incomplete, the notification message only displays the string “You have voted on” without indicating which budget still requires a vote.

This is inconsistent with the message displayed when voting has been completed, which correctly includes the name of the budget.

To Reproduce

1. Go to a participatory budgeting process where voting rules require participants to vote on multiple budgets.
2. Add projects to one budget but leave without voting.
3. Notice that it only displays “You have voted on” without any budget name or information about the pending vote.
4. Complete the vote on the remaining budget.
5. Observe that the message correctly displays “You have voted on [Budget X]”.

Expected behavior

When the voting process is incomplete, the message should clearly indicate which budget still requires a vote:

“You still need to vote on [Budget X]”.

If the participant has completed the vote on one budget but still needs to vote on another, the message should combine both states:

“You have voted on [Budget X] and you still need to vote on [Budget Y]”.

The message should always include the relevant budget names so that participants understand which budgets they have already voted on and which ones still require action.

Extra data

• Decidim Version: 0.33.0.dev
• Decidim installation: Nightly