security, sql: User IDs For Internal User Information

[Fenil-P]

Is your feature request related to a problem? Please describe.
Currently, all internal per-user information is keyed by the username. This is not ideal because it makes it difficult to rename a user without breaking things. It's also not ideal because usernames can be considered personal data, but we need to use them in many places in logging.

Describe the solution you'd like

• Add user_id columns in system tables with role, member or username columns.
• Fix RESTORE from backups as system.users table is missing a column when trying to backup from a previous version.
• Update Authorization functions to use IDs when possible (they receive a user info struct containing both ID and username). The ID lookups will need to be version-gated.
• Update user privileges and their lookups based on IDs instead of usernames (also version gated).
• A long-running migration to give existing users IDs (using a sequence of type OID silimar to postgres).
• Re-enable membership cache which was disabled during changes to authorization functions.
• Fix systems sequences issue where options like min, start and max aren't being respected and the default settings are used.

Additional context
RFC: #77453

relates to #50821

Jira issue: CRDB-14465

Epic CRDB-14475

[rafiss]

@RichardJCai will create new issues to track the remaining work

[ajwerner]

Ref #87079