Test: Invoicing workflow end to end

[clstaudt]

• [x] nice to have: dropdown menu for currencies
• [x] default currency is loaded here

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• [x] "client title" -> "client name"

• [x]  need year 2021

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• [x] 🚨 newly created Contract from the Project form is not selected and not available

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• [x] Contract details not displayed and not editable: #137

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• [x]  form: Tag is not optional

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• [x] after project creation Project is not displayed in the Project Screen

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• [x] layout: make Tag stand out visually

• [x] double ##

[clstaudt]

• [x] order time tracking entries by time before display

• [x] try tweaking table style

[clstaudt]

• [x] "Time Tracked from..." -> "Date Range"

[clstaudt]

• [x] 🚨 Invoice fails to fetch projects

[clstaudt]

• [x] 🚨 saving the invoice does not work

[clstaudt]

• [x] after Client creation from Contract dialog: Remove "Please create a new client" hint / error hint

[clstaudt]

• [x] 🚨 if no time tracking data added, the "New invoice" function should not be available. Tell the user to go to time tracking screen first.

[clstaudt]

• [x] InvoiceTile: show project title

[clstaudt]

• [x] newly created invoice does not have a number @clstaudt

[clstaudt]

• [x] implement Invoice context functions @clstaudt

[clstaudt]

• [x] - time tracking screen: if the DataFrame app.time_tracking_data is not empty, display it as a DataTable