Add a grammar and spell checker assistant (#72)

app/MindWork AI Studio/Components/Pages/GrammarSpelling/AssistantGrammarSpelling.razor

@@ -0,0 +1,11 @@
+@using AIStudio.Tools
+@page "/assistant/grammar-spelling"
+@inherits AssistantBaseCore
+
+<MudTextField T="string" @bind-Text="@this.inputText" Validation="@this.ValidateText" AdornmentIcon="@Icons.Material.Filled.DocumentScanner" Adornment="Adornment.Start" Label="Your input to check" Variant="Variant.Outlined" Lines="6" AutoGrow="@true" MaxLines="12" Class="mb-3" UserAttributes="@USER_INPUT_ATTRIBUTES"/>
+<EnumSelection T="CommonLanguages" NameFunc="@(language => language.NameSelectingOptional())" @bind-Value="@this.selectedTargetLanguage" Icon="@Icons.Material.Filled.Translate" Label="Language" AllowOther="@true" OtherValue="CommonLanguages.OTHER" @bind-OtherInput="@this.customTargetLanguage" ValidateOther="@this.ValidateCustomLanguage" LabelOther="Custom language" />
+<ProviderSelection @bind-ProviderSettings="@this.providerSettings" ValidateProvider="@this.ValidatingProvider"/>
+
+<MudButton Variant="Variant.Filled" Class="mb-3" OnClick="() => this.ProofreadText()">
+    Proofread
+</MudButton>

app/MindWork AI Studio/Components/Pages/GrammarSpelling/AssistantGrammarSpelling.razor.cs

@@ -0,0 +1,84 @@
+using AIStudio.Tools;
+
+namespace AIStudio.Components.Pages.GrammarSpelling;
+
+public partial class AssistantGrammarSpelling : AssistantBaseCore
+{
+    protected override string Title => "Grammar and Spelling Checker";
+    
+    protected override string Description =>
+        """
+        Check the grammar and spelling of a text.
+        """;
+    
+    protected override string SystemPrompt => 
+        $"""
+        You are an expert in languages and their rules. For example, you know how US and UK English or German in
+        Germany and German in Austria differ. You receive text as input. You check the spelling and grammar of
+        this text according to the rules of {this.SystemPromptLanguage()}. You never add information. You
+        never ask the user for additional information. You do not attempt to improve the wording of the text.
+        Your response includes only the corrected text. Do not explain your changes. If no changes are needed,
+        you return the text unchanged.
+        """;
+
+    protected override bool ShowResult => false;
+    
+    protected override IReadOnlyList<ButtonData> FooterButtons => new[]
+    {
+        new ButtonData("Copy corrected text", Icons.Material.Filled.ContentCopy, Color.Default, string.Empty, this.CopyToClipboard),
+    };
+
+    private string inputText = string.Empty;
+    private CommonLanguages selectedTargetLanguage;
+    private string customTargetLanguage = string.Empty;
+    private string correctedText = string.Empty;
+
+    private string? ValidateText(string text)
+    {
+        if(string.IsNullOrWhiteSpace(text))
+            return "Please provide a text as input. You might copy the desired text from a document or a website.";
+        
+        return null;
+    }
+    
+    private string? ValidateCustomLanguage(string language)
+    {
+        if(this.selectedTargetLanguage == CommonLanguages.OTHER && string.IsNullOrWhiteSpace(language))
+            return "Please provide a custom language.";
+        
+        return null;
+    }
+    
+    private string SystemPromptLanguage()
+    {
+        var lang = this.selectedTargetLanguage switch
+        {
+            CommonLanguages.AS_IS => "the source language",
+            CommonLanguages.OTHER => this.customTargetLanguage,
+            
+            _ => $"{this.selectedTargetLanguage.Name()}",
+        };
+
+        if (string.IsNullOrWhiteSpace(lang))
+            return "the source language";
+
+        return lang;
+    }
+
+    private async Task ProofreadText()
+    {
+        if (!this.inputIsValid)
+            return;
+        
+        this.CreateChatThread();
+        var time = this.AddUserRequest(this.inputText);
+        
+        this.correctedText = await this.AddAIResponseAsync(time);
+        await this.JsRuntime.GenerateAndShowDiff(this.inputText, this.correctedText);
+    }
+    
+    private async Task CopyToClipboard()
+    {
+        await this.Rust.CopyText2Clipboard(this.JsRuntime, this.Snackbar, this.correctedText);
+    }
+}