feat: IMAP Driver Integration (#12576)

### Added IMAP integration 

This PR adds support for connecting email accounts via IMAP protocol,
allowing users to sync their emails without OAuth.

#### DB Changes:
- Added customConnectionParams and connectionType fields to
ConnectedAccountWorkspaceEntity

#### UI:
- Added settings pages for creating and editing IMAP connections with
proper validation and connection testing.
- Implemented reconnection flows for handling permission issues.

#### Backend:
- Built ImapConnectionModule with corresponding resolver and service for
managing IMAP connections.
- Created MessagingIMAPDriverModule to handle IMAP client operations,
message fetching/parsing, and error handling.

#### Dependencies:
Integrated `imapflow` and `mailparser` libraries with their type
definitions to handle the IMAP protocol communication.

---------

Co-authored-by: greptile-apps[bot] <165735046+greptile-apps[bot]@users.noreply.github.com>
Co-authored-by: Félix Malfait <felix.malfait@gmail.com>
Co-authored-by: Félix Malfait <felix@twenty.com>

packages/twenty-server/src/engine/core-modules/feature-flag/constants/public-feature-flag.const.ts

@@ -12,6 +12,15 @@ export type PublicFeatureFlag = {
 };
 
 export const PUBLIC_FEATURE_FLAGS: PublicFeatureFlag[] = [
+  {
+    key: FeatureFlagKey.IS_IMAP_ENABLED,
+    metadata: {
+      label: 'IMAP',
+      description:
+        'Easily add email accounts from any provider that supports IMAP (and soon, send emails with SMTP)',
+      imagePath: 'https://twenty.com/images/lab/is-imap-enabled.png',
+    },
+  },
   ...(process.env.CLOUDFLARE_API_KEY
     ? [
         // {

packages/twenty-server/src/engine/core-modules/feature-flag/enums/feature-flag-key.enum.ts

@@ -5,4 +5,5 @@ export enum FeatureFlagKey {
   IS_UNIQUE_INDEXES_ENABLED = 'IS_UNIQUE_INDEXES_ENABLED',
   IS_JSON_FILTER_ENABLED = 'IS_JSON_FILTER_ENABLED',
   IS_AI_ENABLED = 'IS_AI_ENABLED',
+  IS_IMAP_ENABLED = 'IS_IMAP_ENABLED',
 }