[16.0][ADD][POC] budget_spreadsheet

[Saran440]

This PR introduces a new module for the initial step of the budget approval process before government approval.

Concept:

• Before the government approves the budget for each year, the budget manager must have users create projects and request budgets in Excel. After that, the budget manager will summarize and send the budget needs to the government for consideration.

This module facilitates this process. The budget manager can add users to create projects and request budgets in Odoo using a spreadsheet interface similar to Excel.

Step to use:

1. Go to menu Spreadsheets > select Budget Spreadsheet or create new
2. Add users who need to create projects and request budgets in the Contributors field.
3. Add users who need read-only access in the Readers field.
4. Go to Edit > Add project and budget that need
5. The budget manager checks the data and downloads it to Excel to request the budget from the government.
6. After government approval, the budget manager adds the approved amounts to each project.
7. Should there be an action to auto_create_analytic from the spreadsheet?

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Note: After government approval, I am not sure about the next steps. Should there be an action to auto_create_analytic from the spreadsheet and send data to budget_allocation?