Template Materials style differs from the house style content repositories have settled on #57

Noticed while reviewing #50.

The template's Materials section and the protocols in waldronlab/agent-protocols have settled on two different styles. The template writes group headings with a colon, **Input data:**, and separates each item from its description with a dash. Every protocol in the content repository writes **Input data** without the colon, and names each item in backticks followed by a colon:

- **Parameters**
  - `prevalence_threshold`: the minimum fraction of eligible samples in which a
    feature must be detected to be retained. The default is `0.01` (1%).

Neither is wrong, and the validator accepts both. But the template is what a human author copies, and create-protocol now copies it too and then tells the agent to follow house style, so the two styles will keep meeting in review. One of them should change. The backtick-colon form is the one eleven protocols already use, reads better for parameters that an executor has to match by name, and avoids the dash separator, so I would change the template.

The fix is confined to template/protocols/example-protocol/protocol.md, with the same edit to the Materials example in PROTOCOL_STANDARD.md if it shows one.

🤖 Drafted with Claude Code