Auto-increment field

[xixixao]

// schema
experiments: defineEnt()
  .field("name", v.number(), { autoIncrement: true})

// write
ctx.table("experiments").insert({});

but what if you need unique or autoincrement when there's another identifying field (happens often in hieararchies)?

This is a general pattern that would be nice to tackle:

.index("byNumber", ["experimentGroupId", "number"])
.index("byLastUpdateTime", ["experimentGroupId", "lastUpdateTime"])
.index("byAuthorEmail", ["experimentGroupId", "authorEmail"]),