WASM examples (+ backports of new official examples) (#344)

* chg: New build system that uses the officially distributed binaries, bumped version to 8.0.0, simplified git workflow, removed deprecated OpenGL 1.1 functionality.

* chg: Modernize CI workflow, enable SourceLink

- Bump workflow actions to latest majors (Node 24); drop deprecated softprops/action-gh-release@v1
- Trigger push builds on main instead of master
- Create local nuget feed dir before pack (fixes NU1301)
- Enable Microsoft.SourceLink.GitHub for debugging symbols (ref PR #340)

* fix: centralized version data in Directory.build.props, and fixed various interop details that had incorrect function signatures

* chore: updated readme

* fix: version the native extract marker and chain download via DependsOnTargets

The .extracted marker now includes the raylib package name, so bumping
TargetRaylibTag re-extracts the new archive instead of silently keeping
(and packing/copying) the previous version's files.

_PrepareNativeLibrary and _StageWasmNative now depend directly on
_DownloadAndExtractInternal instead of CallTarget-ing it; dependency
targets run in the same project instance, so the resolved properties
(RaylibPackageName etc.) propagate naturally.

* fix: let the binding build for browser-wasm on both net8.0 and net10.0

The net8-era wasm workload (Microsoft.NET.Runtime.WebAssembly.Sdk 8.0.x,
auto-imported for RID browser-wasm) treats every browser-wasm project as
a wasm app: it forces OutputType=Exe after project evaluation (CS5001
for a classlib) and hooks its app-bundle build after Build, which errors
because a library has no assemblies to bundle. Opt Raylib-cs out via
DisableAutoWasmBuildApp (props time, before the workload defaults its
trigger) and pin OutputType back to Library in Directory.Build.targets
(evaluated after the workload props, so the assignment wins). net10's
wasm SDK needs neither workaround.

* chore: readme updated

* chg: simplifying build logic - a simple line in the documentation should save us the code here

* fix: Wrong signature of FrameBufferComplete

* chore: readme update

* feat: samples default to local project reference, and can optionally use the nuget package

* feat: backporting existing raylib-cs examples and new official raylib examples to WASM, adopting raylib's original code style

* chore: readme, gitignore, and targets backport.

* fix: Examples.csproj runs the download task when building locally

* feat: backporting existing raylib-cs examples and new official raylib examples to WASM, adopting raylib's original code style

* chore: readme, gitignore, and targets backport.

* chore: clean up linter warnings

* feat: html harness focuses the example and allows quick navigation with J/K instead.

* chore: readme mentions the property to use nuget vs. the local project reference

* feat: replaced the J/K navigation with good old HTML buttons

* chore: run dotnet format scoped default (was previously scoped to just 'style')

Examples/ExampleRegistry.cs

@@ -0,0 +1,53 @@
+using System.Diagnostics.CodeAnalysis;
+
+namespace Examples;
+
+/// <summary>
+/// Discovers every <see cref="IExample"/> implementation in this assembly via reflection:
+/// <see cref="DesktopExamples"/> (Program.cs) is all of them, <see cref="BrowserExamples"/>
+/// (Web/Host.cs) is everything not marked <see cref="ExcludeFromBrowserAttribute"/>.
+/// Ordering is by category (browser dropdown grouping), then display name.
+/// </summary>
+public static class ExampleRegistry
+{
+    /// <summary>Category order used for the browser dropdown and desktop run-all sequence.</summary>
+    private static readonly string[] CategoryOrder =
+    [
+        "Core",
+        "Shapes",
+        "Models",
+        "Textures",
+        "Text",
+        "Audio",
+        "Shaders",
+    ];
+
+    private static readonly IExample[] AllExamples = DiscoverAll();
+
+    public static readonly IExample[] DesktopExamples = AllExamples;
+
+    public static readonly IExample[] BrowserExamples =
+        Array.FindAll(AllExamples, e => !e.GetType().IsDefined(typeof(ExcludeFromBrowserAttribute), inherit: false));
+
+    [UnconditionalSuppressMessage("Trimming", "IL2026",
+        Justification = "The Examples assembly is rooted via TrimmerRootAssembly in Examples.csproj.")]
+    [UnconditionalSuppressMessage("Trimming", "IL2067",
+        Justification = "Same as IL2026: all example types and their parameterless constructors are rooted.")]
+    private static IExample[] DiscoverAll()
+    {
+        return typeof(IExample).Assembly
+            .GetTypes()
+            .Where(t => typeof(IExample).IsAssignableFrom(t) && t.IsClass && !t.IsAbstract)
+            .Select(t => (IExample)Activator.CreateInstance(t))
+            .OrderBy(e => Array.IndexOf(CategoryOrder, Category(e)))
+            .ThenBy(e => e.Name, StringComparer.OrdinalIgnoreCase)
+            .ToArray();
+    }
+
+    // "Examples.Core" -> "Core"
+    private static string Category(IExample example)
+    {
+        var ns = example.GetType().Namespace ?? "";
+        return ns[(ns.LastIndexOf('.') + 1)..];
+    }
+}