Update API to match resolution of RFD-322

In RFD-322 we reached consensus to update our API design to be ID first[^1]. This issue is to track the work necessary to complete that transition.

Migration

• Update RFD-322's determination section for clarity
• Update instance endpoints first as a PoC of the approach #1957
• Update disk endpoints #2008
• Update networking endpoints #2057
• Update organization endpoints #2050
• Update project endpoints #2050
• Update snapshot endpoints #2347
• Update users and groups #2423
• Update image endpoints
• Update system endpoints
• Update remaining endpoints
• Delete non-V1 endpoints

Cutover

• Improve all the v1 error messages
• Update tests to use v1 APIs
• Mark non-v1 endpoints as deprecated (depends on https://github.com/oxidecomputer/dropshot/pull/503)
• Cleanup authz test ignores
• Update authz test to be able to verify both id and name path requests to the same endpoint.
• Cleanup any TODO-v1 comments
• Cleanup nexus action names as per this comment
• Move all possible contents of a handler into the handler method (context)
• Add comments on each individual property in the selectors to note how they relate to each other (context)
• https://github.com/oxidecomputer/omicron/issues/2409

[^1]: I'm working on synthesizing the discussions and decisions into an an actual determination section