Fully deprecate old recoil (#18210)

## Summary

Removes the `recoil` dependency entirely from `package.json` and
`twenty-front/package.json`, completing the migration to Jotai as the
sole state management library.

Removes all Recoil infrastructure: `RecoilRoot` wrapper from `App.tsx`
and test decorators, `RecoilDebugObserver`, Recoil-specific ESLint rules
(`use-getLoadable-and-getValue-to-get-atoms`,
`useRecoilCallback-has-dependency-array`), and legacy Recoil utility
hooks/types (`useRecoilComponentState`, `useRecoilComponentValue`,
`createComponentState`, `createFamilyState`, `getSnapshotValue`,
`cookieStorageEffect`, `localStorageEffect`, etc.).

Renames all `V2`-suffixed Jotai state files and types to their canonical
names (e.g., `ComponentStateV2` -> `ComponentState`,
`agentChatInputStateV2` -> `agentChatInputState`, `SelectorCallbacksV2`
-> `SelectorCallbacks`), and removes the now-redundant V1 counterparts.

Updates ~433 files across the codebase to use the renamed Jotai imports,
remove Recoil imports, and clean up test wrappers (`RecoilRootDecorator`
-> `JotaiRootDecorator`).

.cursor/rules/README.mdc

@@ -22,7 +22,7 @@ This directory contains Twenty's development guidelines and best practices in th
 
 ### React Development
 - **react-general-guidelines.mdc** - Core React development principles (Auto-attached to React files)
-- **react-state-management.mdc** - State management approaches with Recoil (Auto-attached to state files)
+- **react-state-management.mdc** - State management approaches with Jotai (Auto-attached to state files)
 
 ### Testing & Quality
 - **testing-guidelines.mdc** - Testing strategies and best practices (Auto-attached to test files)

.cursor/rules/architecture.mdc

@@ -7,7 +7,7 @@ alwaysApply: true
 # Twenty Architecture
 
 ## Tech Stack
-- **Frontend**: React 18, TypeScript, Recoil, Styled Components, Vite
+- **Frontend**: React 18, TypeScript, Jotai, Styled Components, Vite
 - **Backend**: NestJS, TypeORM, PostgreSQL, Redis, GraphQL
 - **Monorepo**: Nx workspace with yarn
 

.cursor/rules/react-state-management.mdc

@@ -4,16 +4,20 @@ alwaysApply: false
 ---
 # React State Management
 
-## Recoil Patterns
+## Jotai Patterns
 ```typescript
-// ✅ Atoms for primitive state
-export const currentUserState = atom<User | null>({
+// ✅ Atoms for primitive state (use createAtomState for keyed state with optional persistence)
+import { createAtomState } from '@/ui/utilities/state/jotai/utils/createAtomState';
+
+export const currentUserState = createAtomState<User | null>({
   key: 'currentUserState',
-  default: null,
+  defaultValue: null,
 });
 
-// ✅ Selectors for derived state
-export const userDisplayNameSelector = selector({
+// ✅ Derived atoms for computed state (use createAtomSelector)
+import { createAtomSelector } from '@/ui/utilities/state/jotai/utils/createAtomSelector';
+
+export const userDisplayNameSelector = createAtomSelector({
   key: 'userDisplayNameSelector',
   get: ({ get }) => {
     const user = get(currentUserState);
@@ -21,13 +25,30 @@ export const userDisplayNameSelector = selector({
   },
 });
 
-// ✅ Atom families for dynamic atoms
-export const userByIdState = atomFamily<User | null, string>({
+// ✅ Atom factory pattern for dynamic atoms (use createAtomFamilyState)
+import { createAtomFamilyState } from '@/ui/utilities/state/jotai/utils/createAtomFamilyState';
+
+export const userByIdState = createAtomFamilyState<User | null, string>({
   key: 'userByIdState',
-  default: null,
+  defaultValue: null,
 });
 ```
 
+## Jotai Hooks
+```typescript
+// useAtomState - read and write (like useRecoilState)
+import { useAtomState } from '@/ui/utilities/state/jotai/hooks/useAtomState';
+
+// useAtomStateValue - read only (like useRecoilValue)
+import { useAtomStateValue } from '@/ui/utilities/state/jotai/hooks/useAtomStateValue';
+
+// useSetAtomState - write only (like useSetRecoilState)
+import { useSetAtomState } from '@/ui/utilities/state/jotai/hooks/useSetAtomState';
+```
+
+## Provider
+Jotai works without a Provider by default (unlike Recoil's RecoilRoot). For scoped stores or testing, use `Provider` from `jotai`.
+
 ## Local State Guidelines
 ```typescript
 // ✅ Multiple useState for unrelated state
@@ -74,7 +95,7 @@ const increment = useCallback(() => {
 ```
 
 ## Performance Tips
-- Use atom families for dynamic data collections
-- Implement proper selector caching
-- Avoid heavy computations in selectors
+- Use atom factory pattern (createAtomFamilyState) for dynamic data collections
+- Derived atoms (createAtomSelector) are automatically memoized by Jotai
+- Avoid heavy computations in derived atoms
 - Batch state updates when possible