Apply official naming guidelines to Octobot (#306)

1. The root namespace was changed from `Octobot` to
`TeamOctolings.Octobot`:
> DO prefix namespace names with a company name to prevent namespaces
from different companies from having the same name.
2. `Octobot.cs` was renamed to `Program.cs`:
> DO NOT use the same name for a namespace and a type in that namespace.
3. `IOption`, `Option` were renamed to `IGuildOption` and `GuildOption`
respectively:
> DO NOT introduce generic type names such as Element, Node, Log, and
Message.
4. `Utility` was moved out of the `Services` namespace. It didn't belong
there anyway
5. `Program` static fields were moved to `Utility`
6. Localisation files were moved back to the project source files. Looks
like this fixed `Message.Designer.cs` code generation

---------

Signed-off-by: Octol1ttle <l1ttleofficial@outlook.com>

TeamOctolings.Octobot/Extensions/EmbedBuilderExtensions.cs

@@ -0,0 +1,149 @@
+using Remora.Discord.API;
+using Remora.Discord.API.Abstractions.Objects;
+using Remora.Discord.API.Objects;
+using Remora.Discord.Extensions.Embeds;
+using Remora.Rest.Core;
+
+namespace TeamOctolings.Octobot.Extensions;
+
+public static class EmbedBuilderExtensions
+{
+    /// <summary>
+    ///     Adds a footer representing that an action was performed by a <paramref name="user" />.
+    /// </summary>
+    /// <param name="builder">The builder to add the footer to.</param>
+    /// <param name="user">The user that performed the action whose tag and avatar to use.</param>
+    /// <returns>The builder with the added footer.</returns>
+    public static EmbedBuilder WithActionFooter(this EmbedBuilder builder, IUser user)
+    {
+        var avatarUrlResult = CDN.GetUserAvatarUrl(user, imageSize: 256);
+        var avatarUrl = avatarUrlResult.IsSuccess
+            ? avatarUrlResult.Entity.AbsoluteUri
+            : CDN.GetDefaultUserAvatarUrl(user, imageSize: 256).Entity.AbsoluteUri;
+
+        return builder.WithFooter(
+            new EmbedFooter($"{Messages.IssuedBy}:\n{user.GetTag()}", avatarUrl));
+    }
+
+    /// <summary>
+    ///     Adds a title using the author field, making it smaller than using the title field.
+    /// </summary>
+    /// <param name="builder">The builder to add the small title to.</param>
+    /// <param name="text">The text of the small title.</param>
+    /// <param name="avatarSource">The user whose avatar to use in the small title.</param>
+    /// <returns>The builder with the added small title in the author field.</returns>
+    public static EmbedBuilder WithSmallTitle(
+        this EmbedBuilder builder, string text, IUser? avatarSource = null)
+    {
+        Uri? avatarUrl = null;
+        if (avatarSource is not null)
+        {
+            var avatarUrlResult = CDN.GetUserAvatarUrl(avatarSource, imageSize: 256);
+
+            avatarUrl = avatarUrlResult.IsSuccess
+                ? avatarUrlResult.Entity
+                : CDN.GetDefaultUserAvatarUrl(avatarSource, imageSize: 256).Entity;
+        }
+
+        builder.Author = new EmbedAuthorBuilder(text, iconUrl: avatarUrl?.AbsoluteUri);
+        return builder;
+    }
+
+    /// <summary>
+    ///     Adds a user avatar in the thumbnail field.
+    /// </summary>
+    /// <param name="builder">The builder to add the thumbnail to.</param>
+    /// <param name="avatarSource">The user whose avatar to use in the thumbnail field.</param>
+    /// <returns>The builder with the added avatar in the thumbnail field.</returns>
+    public static EmbedBuilder WithLargeUserAvatar(
+        this EmbedBuilder builder, IUser avatarSource)
+    {
+        var avatarUrlResult = CDN.GetUserAvatarUrl(avatarSource, imageSize: 256);
+        var avatarUrl = avatarUrlResult.IsSuccess
+            ? avatarUrlResult.Entity
+            : CDN.GetDefaultUserAvatarUrl(avatarSource, imageSize: 256).Entity;
+
+        return builder.WithThumbnailUrl(avatarUrl.AbsoluteUri);
+    }
+
+    /// <summary>
+    ///     Adds a guild icon in the thumbnail field.
+    /// </summary>
+    /// <param name="builder">The builder to add the thumbnail to.</param>
+    /// <param name="iconSource">The guild whose icon to use in the thumbnail field.</param>
+    /// <returns>The builder with the added icon in the thumbnail field.</returns>
+    public static EmbedBuilder WithLargeGuildIcon(
+        this EmbedBuilder builder, IGuild iconSource)
+    {
+        var iconUrlResult = CDN.GetGuildIconUrl(iconSource, imageSize: 256);
+        return iconUrlResult.IsSuccess
+            ? builder.WithThumbnailUrl(iconUrlResult.Entity.AbsoluteUri)
+            : builder;
+    }
+
+    /// <summary>
+    ///     Adds a guild banner in the image field.
+    /// </summary>
+    /// <param name="builder">The builder to add the image to.</param>
+    /// <param name="bannerSource">The guild whose banner to use in the image field.</param>
+    /// <returns>The builder with the added banner in the image field.</returns>
+    public static EmbedBuilder WithGuildBanner(
+        this EmbedBuilder builder, IGuild bannerSource)
+    {
+        return bannerSource.Banner is not null
+            ? builder.WithImageUrl(CDN.GetGuildBannerUrl(bannerSource).Entity.AbsoluteUri)
+            : builder;
+    }
+
+    /// <summary>
+    ///     Adds a footer representing that the action was performed in the <paramref name="guild" />.
+    /// </summary>
+    /// <param name="builder">The builder to add the footer to.</param>
+    /// <param name="guild">The guild whose name and icon to use.</param>
+    /// <returns>The builder with the added footer.</returns>
+    public static EmbedBuilder WithGuildFooter(this EmbedBuilder builder, IGuild guild)
+    {
+        var iconUrlResult = CDN.GetGuildIconUrl(guild, imageSize: 256);
+        var iconUrl = iconUrlResult.IsSuccess
+            ? iconUrlResult.Entity.AbsoluteUri
+            : default(Optional<string>);
+
+        return builder.WithFooter(new EmbedFooter(guild.Name, iconUrl));
+    }
+
+    /// <summary>
+    ///     Adds a title representing that the action happened in the <paramref name="guild" />.
+    /// </summary>
+    /// <param name="builder">The builder to add the title to.</param>
+    /// <param name="guild">The guild whose name and icon to use.</param>
+    /// <returns>The builder with the added title.</returns>
+    public static EmbedBuilder WithGuildTitle(this EmbedBuilder builder, IGuild guild)
+    {
+        var iconUrlResult = CDN.GetGuildIconUrl(guild, imageSize: 256);
+        var iconUrl = iconUrlResult.IsSuccess
+            ? iconUrlResult.Entity.AbsoluteUri
+            : null;
+
+        builder.Author = new EmbedAuthorBuilder(guild.Name, iconUrl: iconUrl);
+        return builder;
+    }
+
+    /// <summary>
+    ///     Adds a scheduled event's cover image.
+    /// </summary>
+    /// <param name="builder">The builder to add the image to.</param>
+    /// <param name="eventId">The ID of the scheduled event whose image to use.</param>
+    /// <param name="imageHashOptional">The Optional containing the image hash.</param>
+    /// <returns>The builder with the added cover image.</returns>
+    public static EmbedBuilder WithEventCover(
+        this EmbedBuilder builder, Snowflake eventId, Optional<IImageHash?> imageHashOptional)
+    {
+        if (!imageHashOptional.IsDefined(out var imageHash))
+        {
+            return builder;
+        }
+
+        var iconUrlResult = CDN.GetGuildScheduledEventCoverUrl(eventId, imageHash, imageSize: 1024);
+        return iconUrlResult.IsDefined(out var iconUrl) ? builder.WithImageUrl(iconUrl.AbsoluteUri) : builder;
+    }
+}