Add markdown file support to job steps

src/deepwork/standard_jobs/deepwork_jobs/steps/implement.md

@@ -144,6 +144,12 @@ If a step in the job.yml has `stop_hooks` defined, the generated instruction fil
 
 This alignment ensures the AI agent knows exactly what will be validated and can self-check before completing.
 
+### Using Supplementary Reference Files
+
+Step instructions can include additional `.md` files in the `steps/` directory for detailed examples, templates, or reference material. Reference them using the full path from the project root.
+
+See `.deepwork/jobs/deepwork_jobs/steps/supplemental_file_references.md` for detailed documentation and examples.
+
 ### Step 4: Verify job.yml Location
 
 Verify that `job.yml` is in the correct location at `.deepwork/jobs/[job_name]/job.yml`. The define step should have created it there. If for some reason it's not there, you may need to create or move it.

src/deepwork/standard_jobs/deepwork_jobs/steps/supplemental_file_references.md

@@ -0,0 +1,40 @@
+# Supplementary Reference Files
+
+Step instructions can include additional `.md` files in the `steps/` directory. These supplementary files are useful for:
+
+- Providing detailed examples or templates that would clutter the main instruction file
+- Sharing common reference material across multiple steps
+- Including technical specifications, API documentation, or style guides
+
+## How to Use
+
+1. Place additional `.md` files in the `steps/` directory alongside the main step instruction files
+2. Reference them in your step instructions using the **full path from the project root**
+
+## Example
+
+If you have a job called `my_job` and want to include an API specification template:
+
+1. Create the file at `.deepwork/jobs/my_job/steps/api_spec.md`
+2. Reference it in your step instructions like this:
+
+```markdown
+Use the template in `.deepwork/jobs/my_job/steps/api_spec.md` to structure your API endpoints.
+```
+
+## Path Format
+
+Always use the full relative path from the project root:
+
+```
+.deepwork/jobs/[job_name]/steps/[filename].md
+```
+
+For example:
+- `.deepwork/jobs/competitive_research/steps/competitor_template.md`
+- `.deepwork/jobs/api_design/steps/endpoint_schema.md`
+- `.deepwork/jobs/onboarding/steps/checklist_template.md`
+
+## Benefits
+
+Using supplementary files keeps your main step instructions focused and readable while allowing you to provide detailed reference material when needed. The AI agent can read these files during execution to get additional context.