User accounts

Allows for the creation of user accounts. A few notes on the specifics:

 - Experiments are the main access control objects. If you can view an experiment, you can view all its prompts/scenarios/evals. If you can edit it, you can edit or delete all of those as well.
 - Experiments are owned by Organizations in the database. Organizations can have multiple members and members can have roles of ADMIN, MEMBER or VIEWER.
 - Organizations can either be "personal" or general. Each user has a "personal" organization created as soon as they try to create an experiment. There's currently no UI support for creating general orgs or adding users to them; they're just in the database to future-proof all the ACL logic.
 - You can require that a user is signed-in to see a route using the `protectedProcedure` helper. When you use `protectedProcedure`, you also have to call `ctx.markAccessControlRun()` (or delegate to a function that does it for you; see accessControl.ts). This is to remind us to actually check for access control when we define a new endpoint.

src/components/OutputsTable/NewScenarioButton.tsx

@@ -1,7 +1,7 @@
 import { Button, type ButtonProps, HStack, Spinner, Icon } from "@chakra-ui/react";
 import { BsPlus } from "react-icons/bs";
 import { api } from "~/utils/api";
-import { useExperiment, useHandledAsyncCallback } from "~/utils/hooks";
+import { useExperiment, useExperimentAccess, useHandledAsyncCallback } from "~/utils/hooks";
 
 // Extracted Button styling into reusable component
 const StyledButton = ({ children, onClick }: ButtonProps) => (
@@ -17,6 +17,8 @@ const StyledButton = ({ children, onClick }: ButtonProps) => (
 );
 
 export default function NewScenarioButton() {
+  const { canModify } = useExperimentAccess();
+
   const experiment = useExperiment();
   const mutation = api.scenarios.create.useMutation();
   const utils = api.useContext();
@@ -38,6 +40,8 @@ export default function NewScenarioButton() {
     await utils.scenarios.list.invalidate();
   }, [mutation]);
 
+  if (!canModify) return null;
+
   return (
     <HStack spacing={2}>
       <StyledButton onClick={onClick}>