fix(messaging): honor IMAP/SMTP encryption setting instead of inferring it from the port (#21562)

This pull request makes the IMAP and SMTP encryption setting actually
honor what the user selects.

As per spec there's 3 modes: SSL/TLS (implicit TLS from the start),
STARTTLS (it will attempt TLS but if the server doesn't support it, it
gracefully falls back to plaintext), NONE (plaintext)

Current implementation had a boolean flag for this, this replaces it
with the 3 modes

Upgrade command to migrate all existing accounts, to not risk breaking
anyone's existing account in production we map each account to the mode
that matches its current behavior, so nothing changes on the wire

/closes #21300

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Co-authored-by: Charles Bochet <charles@twenty.com>

packages/twenty-server/src/database/commands/upgrade-version-command/instance-commands.constant.ts

@@ -70,6 +70,7 @@ import { RenameIsUiReadOnlyToIsUiEditableFastInstanceCommand } from 'src/databas
 import { BackfillNonUiCreatableStandardSystemObjectsSlowInstanceCommand } from 'src/database/commands/upgrade-version-command/2-13/2-13-instance-command-slow-1781277480000-backfill-non-ui-creatable-standard-system-objects';
 import { CommandMenuItemOverridableEntityFastInstanceCommand } from 'src/database/commands/upgrade-version-command/2-13/2-13-instance-command-fast-1781253016028-command-menu-item-overridable-entity';
 import { SetTableWidgetViewsVisibilityToWorkspaceSlowInstanceCommand } from 'src/database/commands/upgrade-version-command/2-14/2-14-instance-command-slow-1781515653781-set-table-widget-views-visibility-to-workspace';
+import { BackfillConnectionSecuritySlowInstanceCommand } from 'src/database/commands/upgrade-version-command/2-15/2-15-instance-command-slow-1781461753981-backfill-connection-security';
 
 export const INSTANCE_COMMANDS = [
   AddViewFieldGroupIdIndexOnViewFieldFastInstanceCommand,
@@ -142,4 +143,5 @@ export const INSTANCE_COMMANDS = [
   BackfillNonUiCreatableStandardSystemObjectsSlowInstanceCommand,
   CommandMenuItemOverridableEntityFastInstanceCommand,
   SetTableWidgetViewsVisibilityToWorkspaceSlowInstanceCommand,
+  BackfillConnectionSecuritySlowInstanceCommand,
 ];