* Update shared vpc config for project factory and project module for more granular Shared VPC configuration
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Co-authored-by: Ludovico Magnocavallo <ludomagno@google.com>
* improve project factory example
* light refactor of project modules shared vpc internals and docs
* add support for subnet-level grants on host project
* [module/project] Grant IAM rights to service identities based on used services in host project
* [blueprints/factories/project-factory] enable granting IAM permissions in host VPC for service identities directly or by specifying services in use
* fix IAM in examples
* WIP
* fix service identities IAM example
* design principles
* toc anchors
* fix ordering
* style guide
* checks
* example tests
* tests and tools
* fix project example test
* address typos
* address comments
* address last comments