Bug: Fast check cannot infer type from this export

[marvinhagemeister]

Fast check should be able to infer the type here:

export const middlewareMarker = 'middlewareMarker' as 'middlewareMarker' & {
  __brand: 'middlewareMarker';
};

It's a simple as <Type> expression so the expected output should be:

export const middlewareMarker: 'middlewareMarker' & {
  __brand: 'middlewareMarker';
};

Error:

error[missing-explicit-type]: missing explicit type in the public API
  --> /Users/marvinh/dev/oss/trpc/packages/server/src/core/internals/utils.ts:45:14
   | 
45 | export const middlewareMarker = 'middlewareMarker' as 'middlewareMarker' & {
   |              ^^^^^^^^^^^^^^^^ this symbol is missing an explicit type
   = hint: add an explicit type annotation to the symbol

  info: all symbols in the public API must have an explicit type
  docs: https://jsr.io/go/slow-type-missing-explicit-type

Version: Deno 1.41.1

[marvinhagemeister]

I addressed these things in the DTS transform for JSR but it looks like it errors out earlier in fast check. For named exports we can basically copy the type annotation from the TsAsExpression and for default exports we need to create a temporary variable and copy the type annotation to there.