Add new "common" schematic to share configurations for all schematics at once

### Command

generate

### Description

Implement an internal artifact to commonize the configuration of schematics so that all schematics can share a common configuration by default, and override on a per-artifact basis if needed. Currently, all configurations are duplicated, and while not that annoying to deal with for a single collection, it can quickly add up when using several collections.

### Describe the solution you'd like

Actual :
```json
{
"schematics": {
"@schematics/angular:component": { "skipSelector": true },
"@schematics/angular:directive": { "skipSelector": true },
"@schematics/angular:pipe": { "skipSelector": true }
}
}
```
Proposed :
```json
{
"schematics": {
"@schematics/angular:common": { "skipSelector": true }
}
}
```

This new `common` schematic would contain either
- only fields that are common to all artifacts
- All fields possible, even if not applicable to certain artifacts

Resolving would follow this pattern :
- Look for common artifact schematic value
- If existing, apply value
- If all fields are possible : also check if value is applicable to artifact
- Look for direct artifact schematic value
- Override value

### Describe alternatives you've considered

Doing it by hand as already done today is the only solution

Beginne mit dem generate-Befehl und dem Pfad zur Auflösung der Schematic-Konfiguration. Vergleiche die vorgeschlagene gemeinsame Konfiguration mit der aktuellen Konfiguration pro Artefakt und definiere anschließend, wie gemeinsame Werte angewendet werden und wie direkte Artefaktwerte sie überschreiben. Erledigt ist dies, wenn Schematics gemeinsame Standardwerte erben können und dabei Überschreibungen pro Artefakt erhalten bleiben.

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