### Steps to reproduce

1. Log in as a user with WP creation and add own unit costs permissions

2. Go to any WP list

3. Right click on any WP

4. Select 'Log unit costs'


### What is the buggy behaviour?

* User can save any type of input


### What is the expected behaviour?

From UX UI meeting group

1. Begin of the deletion The input should be float or int.

2. End of the deletion Pragmatic quick-fix: Change the field to a Begin of the insertionfield with a regex on it to allow onlyEnd of the insertion number Begin of the insertionspecific stuff.

1. This needed to be done with a regex because number fields are per definition not sensitive to locales resulting in wrong results with other locales then English


End of the insertion Begin of the deletion field.


End of the deletion ###

### Screenshots and other files

<img class="op-uc-image op-uc-image_inline" src="/api/v3/attachments/919382/content">

### Environment information

**OpenProject version**

Core build

[eef7c5eccf63b767ec90e4cfac91aa5ce9ca2b62](https://qa.openproject-stage.com/external_redirect?url=https%3A%2F%2Fgithub.com%2Fopf%2Fopenproject%2Fcommits%2Feef7c5eccf63b767ec90e4cfac91aa5ce9ca2b62)

Product version

[ecfbdd2facf738f725a89cda20e6909aaa4b155f](https://qa.openproject-stage.com/external_redirect?url=https%3A%2F%2Fgithub.com%2Fopf%2Fsaas-openproject%2Fcommits%2Fecfbdd2facf738f725a89cda20e6909aaa4b155f)

Core version

OpenProject 17.2.0

**Browser**

* [ ] Chrome
* [x] Firefox
* [ ] Safari
* [ ] Mobile Safari
* [ ] Other (please specify)

**Operating System**

* [x] Windows
* [ ] Mac OS X
* [ ] Mobile iOS
* [ ] Mobile Android
* [ ] Linux (please specify distro)
* [ ] Chrome OS
* [ ] Other (please specify)