Phase 1: Model update + file-level parser (text-only steps)

- Update Roux.Types: add SectionBodyItem (SecStep/SecComment/SecNote),
  StepEndComment, remove StepNote (notes are now section-level)
- Rewrite Roux.Parser using Parsec for inline elements, text-splitting
  for file-level structure
- Handle full-line -- comments, > notes, = Name = section headers
- Handle = Name (w/ and w/o closing =), == Name == variations
- Handle end-of-line backslash line breaks within steps
- Update tests to match new model + 3 EasyPancakes integration tests
- Add expectTextStep helper at module level

cooklang-examples/CoffeeSouffle.cook

@@ -0,0 +1,12 @@
+-- make caramel
+
+Crack the @egg yoke{1} into a bowl, then add the @condenced milk{125%g} and @instant coffee{3tsp}, and mix until a nice caramel is formed. Do not allow to bubble.
+
+Pour into a #bowl and leave to cool down for ~{15%minutes}.
+
+heat @water{1,1/2cups} and @gelatine{3tsp} then stir till gelatine is dissolved completely.Once gelatine is colled down mix it with the caramel.
+
+Beat @eggwhite{1} until formy. Then mix the whites bit by bit to the the gelatinecaramel mixture.
+
+
+Pour into a #puddingbowl and leave in fridge for 2 hours minimum. Add some @cashew{60%g} and enjoy!