Remove remaining em-dashes from Hello nf-core

Strip all remaining em-dashes from the hello nf-core documentation,
replacing them with periods, commas, or colons as appropriate for
cleaner, more straightforward technical writing.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <[email protected]>

Author: pinin4fjords

docs/hello_nf-core/02_rewrite_hello.md

@@ -280,7 +280,7 @@ Learn how to make a simple workflow composable as a prelude to making it nf-core
 ## 2. Make the original Hello Nextflow workflow composable
 
 Before we can integrate our workflow into the nf-core scaffold, we need to make it **composable**.
-A composable workflow must be called from a parent workflow—it cannot run on its own—which is exactly how the nf-core template is structured.
+A composable workflow must be called from a parent workflow. It cannot run on its own, which is exactly how the nf-core template is structured.
 
 ### What does the Hello Nextflow workflow do?
 

docs/hello_nf-core/04_make_module.md

@@ -761,7 +761,7 @@ You now know how to create nf-core modules! You learned the three key patterns t
 - **`ext.prefix`** standardizes output file naming
 - **Centralized configuration** in `modules.config` keeps modules reusable
 
-By transforming `cowpy` step-by-step, you developed a deep understanding of these patterns—making you equipped to work with, debug, and create nf-core modules.
+By transforming `cowpy` step-by-step, you developed a deep understanding of these patterns, making you equipped to work with, debug, and create nf-core modules.
 In practice, you'll use `nf-core modules create` to generate properly structured modules with these patterns built in from the start.
 
 Finally, you learned how to contribute modules to the nf-core community, making tools available to researchers worldwide while benefiting from ongoing community maintenance.

docs/hello_nf-core/summary.md

@@ -4,7 +4,7 @@ Congratulations on completing the Hello nf-core training course! 🎉
 
 ## Your journey
 
-You started with a simple Nextflow workflow from the Hello Nextflow course—a straightforward pipeline that processed greetings through a few steps and added some ASCII art.
+You started with a simple Nextflow workflow from the Hello Nextflow course: a straightforward pipeline that processed greetings through a few steps and added some ASCII art.
 Through five parts, you've transformed that basic workflow into a production-ready nf-core pipeline.
 
 ### What you built