## Commit 1
[FIX] point_of_sale, pos_sale: fix product loading in POS

Before this commit, when loading additional products after the initial
load, the PoS were not receiving all necessary data related to the
products, for example product's precomputed taxes objects.

This commit add a method which will load all necessary data for the
products when loading them in the PoS.

What's more, when a product was loaded via barcode, it didn't yet have
its associated pricelists, as these were loaded in another RPC. This
commit unifies data reception via a single RPC.

Loyalty cards are not longer loaded at the beginning of the PoS since
they are loaded each time a partner is selected. Loyalty cards doesn't
works with offline mode anyway since some backend check must be done
before validating them.

Some debug information about loading times and records is now printed
in the console when the PoS is started in debug mode.

IndexedDB method is now debounced to avoid calling it too often when the
PoS is started. The create method is also batched to avoid putting large
amount of data in IndexedDB at once.

Loaded data includes:
- `product.product`
- `product.template`
- `product.combo`
- `product.combo.item`
- `product.uom`
- `product.pricelist`
- `product.pricelist.item`
- `product.template.attribute.value`
- `product.template.attribute.line`
- `account.tax`

## Commit 2

[PERF] point_of_sale: pricelist computations
Before this commit, when we were trying to compute pricelist item for
a product, we were iterating over all pricelist items of the pricelist
and checking if the product was in the item or if the item didn't
have any product set. This was very inefficient, especially when
there were many pricelist items and products.

This commit add a pre-computation of pricelist items for general rules
which eliminates the need to calculate rules on the fly.