vfs_vector: Add VFS backend for std::array

Allows using constexpr/static const data with VFS.

src/core/file_sys/vfs_vector.h

@@ -8,6 +8,58 @@
 
 namespace FileSys {
 
+// An implementation of VfsFile that is backed by a statically-sized array
+template <std::size_t size>
+class ArrayVfsFile : public VfsFile {
+public:
+    ArrayVfsFile(std::array<u8, size> data, std::string name = "", VirtualDir parent = nullptr)
+        : data(std::move(data)), name(std::move(name)), parent(std::move(parent)) {}
+
+    std::string GetName() const override {
+        return name;
+    }
+
+    std::size_t GetSize() const override {
+        return size;
+    }
+
+    bool Resize(std::size_t new_size) override {
+        return false;
+    }
+
+    std::shared_ptr<VfsDirectory> GetContainingDirectory() const override {
+        return parent;
+    }
+
+    bool IsWritable() const override {
+        return false;
+    }
+
+    bool IsReadable() const override {
+        return true;
+    }
+
+    std::size_t Read(u8* data_, std::size_t length, std::size_t offset) const override {
+        const auto read = std::min(length, size - offset);
+        std::memcpy(data_, data.data() + offset, read);
+        return read;
+    }
+
+    std::size_t Write(const u8* data, std::size_t length, std::size_t offset) override {
+        return 0;
+    }
+
+    bool Rename(std::string_view name) override {
+        this->name = name;
+        return true;
+    }
+
+private:
+    std::array<u8, size> data;
+    std::string name;
+    VirtualDir parent;
+};
+
 // An implementation of VfsFile that is backed by a vector optionally supplied upon construction
 class VectorVfsFile : public VfsFile {
 public: