fix(shared): make WizardDraftRepository AOT-safe (v3.9.1 hotfix)

Production regression in 3.9.0: Telegram bot silently dropped every update.
WizardDraftRepository.GetActiveAsync was called on every Telegram update
(via UpdateRouter -> TryGetWizardContext) and threw
System.PlatformNotSupportedException in NativeAOT, because Dapper.AOT 1.0.48
only generates interceptors for the (sql, object?) extension overloads and
NOT for the (CommandDefinition) overload. The runtime then fell back to
Dapper.SqlMapper.CreateParamInfoGenerator, which uses Reflection.Emit and
fails on AOT. TelegramBotService swallowed the exception, so /newsession
appeared to start but no button press reached the wizard and no session was
created.

Two related changes in WizardDraft:

1. Switched WizardDraftRepository.* from 'new CommandDefinition(sql, params,
   cancellationToken: ct)' to the direct 'connection.Query*(sql, params)'
   overload, matching the working pattern in JoinSessionHandler. Dapper.AOT
   now generates CommandFactory30<WizardDraft> + RowFactory17<WizardDraft> +
   QuerySingleOrDefaultAsync37<WizardDraft> for all four methods.

2. WizardDraft.CreatedAt/UpdatedAt/ExpiresAt are now DateTime (UTC) instead
   of DateTimeOffset. AOT RowFactory calls reader.GetDateTime() directly and
   does not perform DateTime -> DateTimeOffset conversion; the previous type
   raised InvalidCastException on the very first wizard_drafts query.

All 588/590 tests pass (2 pre-existing skipped, +5 new AOT regression tests
in WizardDraftRepositoryAotShapeTests). dotnet format clean.

Bumps: 3.9.0 -> 3.9.1.

Note: GetOwnerClubsAsync (Telegram/Discord), DiscordPermissionLookup, and
DiscordWizardInteractionModule.GetOwnerClubsAsync still use CommandDefinition
and will hit the same Reflection.Emit AOT failure when the user reaches the
PickClub visibility step. Follow-up in 3.9.2.

src/GmRelay.DiscordBot/Features/Sessions/Wizard/DiscordWizardCommand.cs

@@ -115,9 +115,9 @@ public sealed class DiscordWizardCommand : ApplicationCommandModule<SlashCommand
             Step = NormalizeMode(mode) is { } m && m == WizardCreationType.Pool
                 ? WizardStepNames.Title
                 : WizardStepNames.Type,
-            CreatedAt = DateTimeOffset.UtcNow,
-            UpdatedAt = DateTimeOffset.UtcNow,
-            ExpiresAt = DateTimeOffset.UtcNow.AddHours(24),
+            CreatedAt = DateTime.UtcNow,
+            UpdatedAt = DateTime.UtcNow,
+            ExpiresAt = DateTime.UtcNow.AddHours(24),
         };
         // If the user passed `mode=pool` we pre-seed the payload so the
         // wizard's own branching lands on the pool flow.
@@ -147,7 +147,7 @@ public sealed class DiscordWizardCommand : ApplicationCommandModule<SlashCommand
             var (text, actions) = WizardStepViewBuilder.Build(draft, payload);
             var msgId = await _messenger.SendDraftMessageAsync(draft, text, actions, ct);
             draft.DraftMessageId = msgId;
-            draft.UpdatedAt = DateTimeOffset.UtcNow;
+            draft.UpdatedAt = DateTime.UtcNow;
             await _drafts.UpsertAsync(draft, ct);
 
             await Context.Interaction.ModifyResponseAsync(msg =>

src/GmRelay.DiscordBot/Features/Sessions/Wizard/DiscordWizardSubmitter.cs

@@ -97,7 +97,7 @@ public sealed class DiscordWizardSubmitter
                 _contextStore.Remove(draft.Id);
                 return;
             }
-            draft.UpdatedAt = DateTimeOffset.UtcNow;
+            draft.UpdatedAt = DateTime.UtcNow;
             await _drafts.UpsertAsync(draft, ct);
             // The full exception (with stack trace, Postgres constraint
             // name, sometimes partial SQL) is already logged server-side