fix: show filename information in legacy_recursive_reactive_block

[paoloricciuti]

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As per discord discussion this add the name of the file the warning is generated from to legacy_recursive_reactive_block. The name is only available in dev but that's not a problem since the warning is only thrown in DEV anyway. If for some reason FILENAME should not be there i've used "a file (we can't know which one)" as a fallback (not sure about the parenthesis tbf).

Simon originally had the idea of passing the filename and position with via the ast but the run function is meant to be visible in the code so i think this approach is more than enough.

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🦋 Changeset detected

Latest commit: 7e4de19

The changes in this PR will be included in the next version bump.

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[dummdidumm]

Looks good, just needs a changeset and we're good to merge

[paoloricciuti]

Looks good, just needs a changeset and we're good to merge

Lol even when the title is good i mess the changeset