[josephjclark]

Short Description

Fixes an issue where we fail to extract source from the sourcemap and throw a cryptic error.

The problem was basically:

• The worker compiles each step under a filename corresponding to the step name, eg, step.js
• The sourcemap was using a hard-coded filename of "src.js" to find files in the sourcemap
• Thus an exception was being thrown and generating headaches

Fixes #1045

AI Usage

Please disclose how you've used AI in this work (it's cool, we just want to know!):

• Code generation (copilot but not intellisense)
• Learning or fact checking
• Strategy / design
• Optimisation / refactoring
• Translation / spellchecking / doc gen
• Other
• I have not used AI

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