Merged PR 2607: Propagates and exposes multiple dimension handling for KPIs

# Description

This PR ensures the propagation of the dimensions for KPIs across the key aggregating and exposing models. Additionally, provides these 2 new fields in reporting while **not affecting the current data display**, thus it's safe to work in the PBI report without needing to work in 2 PRs in parallel.

**Changes:**

**1 - Intermediate, `int_mtd_vs_previous_year_metrics`:**

* Removes the temporary filter on `where dimension in ({{ production_dimensions }})`. This will be applied directly to reporting later. This ensures that the new dimension on customer segmentation is fully available only within intermediate.
* Adds `dimension` and `dimension_value` granularity. This includes: 1) adding these fields, 2) joining by these fields with all the source CTEs containing the source models with metrics - which in turn needs the change of the dates model - and 3) joining by these fields in the self-join to compute the incremental vs. previous year.
* Changes on the schema file

**2 - Intermediate, `int_mtd_aggregated_metrics`:**

* Adds `dimension` and `dimension_value` granularity. This includes only adding these fields.
* Changes on the schema file

**3 - Reporting, `mtd_aggregated_metrics`:**

* Adds the filter removed on `int_mtd_vs_previous_year_metrics`. This ensures that only the Global dimension is available for the reporting, thus **no changes from user POV**.
* Adds `dimension` and `dimension_value` granularity. This includes only adding these fields
* Changes on the schema file

# 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: #19325

models/reporting/general/schema.yaml

@@ -302,7 +302,7 @@ models:
   - name: mtd_aggregated_metrics
     description: |
       This model aggregates the historic information of our business by providing
-      different metrics computed at global level.
+      different metrics computed at global and dimension level.
       It's the main source of information for the Main KPIs reporting, specifically
       on the MTD (Month To Date) and the Monthly Overview.
 
@@ -311,6 +311,8 @@ models:
           combination_of_columns:
             - date
             - metric
+            - dimension
+            - dimension_value
 
     columns:
       - name: year
@@ -361,6 +363,21 @@ models:
         tests:
           - not_null
 
+      - name: dimension
+        data_type: string
+        description: The dimension or granularity of the metrics.
+        tests:
+          - accepted_values:
+                values:
+                - global
+                - by_number_of_listings
+      
+      - name: dimension_value
+        data_type: string
+        description: The value or segment available for the selected dimension.
+        tests:
+          - not_null
+
       - name: previous_year_date
         data_type: date
         description: |