**What**
- Selects the correct tax line for an item given a calculation context.
**For later PR**
- Consider optimizations. Some thoughts:
- Even with global sales the number of rates in the DB is not likely to grow beyond ~1000.
- Can large orders with hundreds of items optimize somehow?
- Does it make sense to write a custom SQL query to do this?
- Support combined rate.
**Test cases covered**
The selection of tax rates take the following priority:
1. specific product rules - province
2. specific product type rules - province
3. default province rules
4. specific product rules - country
5. specific product type rules - country
6. default country rules
There are test cases for each of them under the following data seed structure:
### **US**
- **Default Rate**: 2%
- **Sub-Regions**
- CA
- Default Rate: 5%
- Overrides
- Reduced rate (for 3 product ids): 3%
- Reduced rate (for product type): 1%
- NY
- Default rate: 6%
- FL
- Default rate: 4%
- **Overrides**
- None
### **Denmark**
- **Default rate:** 25%
- **Sub-Regions**
- None
- **Overrides**
- None
### **Germany**
- **Default Rate:** 19%
- **Sub-Regions**
- None
- **Overrides:**
- Reduced Rate (for product type) - 7%
### **Canada**
- **Default rate**: 5%
- **Sub-Regions**
- QC
- Default rate: 2%
- Overrides:
- Reduced rate (for same product type as country reduced rate): 1%
- BC
- Default rate: 2%
- **Overrides**
- Reduced rate (for product id) - 3%
- Reduced rate (for product type) - 3.5%
**What**
> [!NOTE]
> I can see this pr becoming huge, so I d like to get this partial one merged 👍
- Fixes shared connection usage (mikro orm compare the instance to its own package and therefore was resulting in not trully reusing the provided connection leading to exhausting the connection pool as multiple connections was created and end up not being all destroyed properly under the hood, discovered in my integration tests)
- Create shipping options method implementation
- DTO's definition and service interface update
- integration tests
- Re work of the indexes with new util update
- Test runner utils to remove a big chunk of the boilerplate of the packages integrations
FIXES CORE-1742
