[IMP] product_catalog_tree: add button to load vendor min qty in list catalog

[fw-bot-adhoc]

Problem

In the list-view catalog the + button (increase_quantity) always adds 1
unit. The kanban catalog instead suggests the vendor's min_qty on the
first add (see purchase product_catalog/kanban_record.js → addProduct).

As a consequence, adding a product whose vendor min_qty is greater than the
added quantity from the list catalog selects no seller, and the price falls
back to the product cost — while doing the same from the kanban catalog applies
the vendor price. Same product, different price depending on the view used.

Change

• Expose product_catalog_min_qty on the catalog row (taken from the catalog
  payload min_qty).
• Add a dedicated button add_catalog_min_qty that mirrors the kanban
  behaviour: on the first add it uses the vendor min_qty (so the vendor price
  applies instead of the cost); once the line already exists it adds one, like
  the + button. The button is only shown when the vendor min_qty is greater
  than 1.
• Add tests (skipped when purchase is not installed).

The existing + button keeps its behaviour unchanged.

Forward-Port-Of: #908

[roboadhoc]

[fw-bot-adhoc]

@jcadhoc @les-adhoc cherrypicking of pull request #908 failed.

• 04bede0 <- on this commit
• 5e5ddb7

stdout:

Auto-merging product_catalog_tree/__manifest__.py
CONFLICT (content): Merge conflict in product_catalog_tree/__manifest__.py
Auto-merging product_catalog_tree/models/product_product.py
Auto-merging product_catalog_tree/views/product_product_views.xml

Either perform the forward-port manually (and push to this branch, proceeding as usual) or close this PR (maybe?).

you can use git-fw to re-do the forward-port for you locally.

⚠️ after resolving this conflict, you will need to merge it via @roboadhoc.

More info at https://github.com/odoo/odoo/wiki/Mergebot#forward-port

[fw-bot-adhoc]

@jcadhoc @les-adhoc this forward port of #908 is awaiting action (not merged or closed).

[fw-bot-adhoc]

@jcadhoc @les-adhoc this forward port of #908 is awaiting action (not merged or closed).

[fw-bot-adhoc]

@jcadhoc @les-adhoc this forward port of #908 is awaiting action (not merged or closed).

[les-adhoc]

@roboadhoc r+ nobump

[roboadhoc]

@jcadhoc @les-adhoc unable to stage: All commits must have author and committer email, missing email on 9079b8d indicates the authorship is most likely incorrect.

[fw-bot-adhoc]

@jcadhoc @les-adhoc this forward port of #908 is awaiting action (not merged or closed).

[les-adhoc]

@roboadhoc r+ nobump