[experiment] add alternative wasm sqlite3 implementation available via build-tag (#2863)

This allows for building GoToSocial with [SQLite transpiled to WASM](https://github.com/ncruces/go-sqlite3) and accessed through [Wazero](https://wazero.io/).

vendor/github.com/tetratelabs/wazero/experimental/sys/error.go

@@ -0,0 +1,45 @@
+package sys
+
+import (
+	"io"
+	"io/fs"
+	"os"
+)
+
+// UnwrapOSError returns an Errno or zero if the input is nil.
+func UnwrapOSError(err error) Errno {
+	if err == nil {
+		return 0
+	}
+	err = underlyingError(err)
+	switch err {
+	case nil, io.EOF:
+		return 0 // EOF is not a Errno
+	case fs.ErrInvalid:
+		return EINVAL
+	case fs.ErrPermission:
+		return EPERM
+	case fs.ErrExist:
+		return EEXIST
+	case fs.ErrNotExist:
+		return ENOENT
+	case fs.ErrClosed:
+		return EBADF
+	}
+	return errorToErrno(err)
+}
+
+// underlyingError returns the underlying error if a well-known OS error type.
+//
+// This impl is basically the same as os.underlyingError in os/error.go
+func underlyingError(err error) error {
+	switch err := err.(type) {
+	case *os.PathError:
+		return err.Err
+	case *os.LinkError:
+		return err.Err
+	case *os.SyscallError:
+		return err.Err
+	}
+	return err
+}