Merged PR 4504: Onboarding MRR + Visualisation changes

# Description

Changes:
* Adds Onboarding MRR
* Refactors exclusion code for ongoing month / invoicing cycle
* Adds sign format on relative differences

# Checklist

- [X] The edited models and dependants run properly with production data.
- [X] The edited models are sufficiently documented.
- [X] The edited models contain PK tests, and I've ran and passed them.
- [X] I have checked for DRY opportunities with other models and docs.
- [X] I've picked the right materialization for the affected models.

# Other

- [ ] Check if a full-refresh is required after this PR is merged.

Related work items: #27609, #27805

models/reporting/general/schema.yml

@@ -2131,3 +2131,38 @@ models:
         description: |
           Achievement rate between the current year YTD and the EOFY target. It can be null
           if the target is not available.
+
+      - name: rel_diff_with_sign_current_month_mtd_vs_previous_month_eom
+        data_type: numeric
+        description: |
+          Relative difference between the current month MTD and the previous month EOM, 
+          with a sign to represent if the relative difference is good (positive) or bad 
+          (negative) for our business.
+
+      - name: rel_diff_with_sign_current_month_mtd_vs_previous_year_mtd
+        data_type: numeric
+        description: |
+          Relative difference between the current month MTD and the previous year MTD, 
+          with a sign to represent if the relative difference is good (positive) or bad 
+          (negative) for our business.
+
+      - name: rel_diff_with_sign_current_ytd_vs_previous_ytd
+        data_type: numeric
+        description: |
+          Relative difference between the current year YTD and the previous year YTD, 
+          with a sign to represent if the relative difference is good (positive) or bad 
+          (negative) for our business.
+
+      - name: rel_diff_with_sign_current_month_mtd_vs_eom_target
+        data_type: numeric
+        description: |
+          Relative difference between the current month MTD and the EOM target, 
+          with a sign to represent if the relative difference is good (positive) or bad 
+          (negative) for our business.
+
+      - name: rel_diff_with_sign_current_ytd_vs_ytd_target
+        data_type: numeric
+        description: |
+          Relative difference between the current year YTD and the YTD target, 
+          with a sign to represent if the relative difference is good (positive) or bad 
+          (negative) for our business.