[massive store] Lazy removal of constraints and metadata indexes
They should not be removed during store's init, because we may want to query the
database with its index between store creation and call to prepare_insert* (e.g.
to build the extid2eid map).
Along the way:
* rename drop_metadata_constraints into drop_metadata_indexes, because that's
what it does
* rework a bit impacted tests
Closes #15538359
CSS Coding Standards
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(Draft, to be continued)
:Naming: camelCase
Indentation rules
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- 2 espaces avant les propriétés
- pas d'espace avant les ":", un espace après
- 1 seul espace entre les différentes valeurs pour une même propriété
Documentation
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Please keep rules semantically linked grouped together, with a comment about
what they are for.
Recommendation
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- Try to use existing classes rather than introduce new ones
- Keep things as simple as possible while in the framework
- Think about later customization by application
- Avoid introducing a new CSS file for a few lines of CSS, at least while the
framework doesn't include packing functionalities