Add init weapon scraper

BlueLaminate/BlueLaminate.Scraper/Wiki/WikiPageFetcher.cs

@@ -0,0 +1,51 @@
+using System.Text.Json;
+using HtmlAgilityPack;
+
+namespace BlueLaminate.Scraper.Wiki;
+
+/// <summary>
+/// Fetches a rendered page from the Counter-Strike Fandom wiki, shared by all
+/// wiki scrapers.
+///
+/// The rendered HTML pages sit behind Cloudflare, which 403s .NET's TLS
+/// fingerprint regardless of headers. The MediaWiki <c>action=parse</c> API is
+/// not challenged, so we fetch the same content as JSON from there and return
+/// the embedded HTML as a parsed document.
+/// </summary>
+public sealed class WikiPageFetcher
+{
+    private const string ApiBase = "https://counterstrike.fandom.com/api.php";
+
+    private readonly HttpClient _http;
+
+    public WikiPageFetcher(HttpClient http) => _http = http;
+
+    /// <summary>Loads a wiki page (e.g. "Weapons") as a parsed HTML document.</summary>
+    public async Task<HtmlDocument> LoadAsync(string page, CancellationToken ct = default)
+    {
+        var url = $"{ApiBase}?action=parse&page={Uri.EscapeDataString(page)}&prop=text&format=json";
+
+        using var resp = await _http.GetAsync(url, ct);
+        resp.EnsureSuccessStatusCode();
+
+        await using var stream = await resp.Content.ReadAsStreamAsync(ct);
+        using var json = await JsonDocument.ParseAsync(stream, cancellationToken: ct);
+
+        if (json.RootElement.TryGetProperty("error", out var error))
+        {
+            var info = error.TryGetProperty("info", out var i) ? i.GetString() : "unknown error";
+            throw new InvalidOperationException($"Wiki API returned an error for page '{page}': {info}");
+        }
+
+        var html = json.RootElement
+            .GetProperty("parse")
+            .GetProperty("text")
+            .GetProperty("*")
+            .GetString()
+            ?? throw new InvalidOperationException($"Wiki API response for page '{page}' had no parsed text.");
+
+        var doc = new HtmlDocument();
+        doc.LoadHtml(html);
+        return doc;
+    }
+}