Fix dependabot-burner: add missing update_project and status update instructions

[Copilot]

Campaign workflow created issues but failed to add them to the project board or post status updates. Instructions used placeholder values and lacked explicit guidance.

Changes

Replace placeholder URLs with concrete values

• All update_project calls now use https://github.com/orgs/githubnext/projects/144
• Applies to PR updates (line 45), issue updates (line 65), and status updates (line 77)

Add explicit field values for issue project updates

2. Capture the returned temporary ID, then immediately call `update_project(...)`:
   - `project`: https://github.com/orgs/githubnext/projects/144
   - `content_type`: "issue"
   - `content_number`: "<temporary_id>"
   - `fields`:
     - Set `status`: "In Progress"
     - Set `campaign_id`: "dependabot-burner"
     - Set `target_repo`: "githubnext/gh-aw"
     - Set `worker_workflow`: "dependabot"

Add "Final step" section for project status updates

### Final step

After all work is complete, call `create_project_status_update` exactly once:
- `project`: https://github.com/orgs/githubnext/projects/144
- `status`: "ON_TRACK" (or "INACTIVE" if no work was found)
- `start_date`: today's date (YYYY-MM-DD format)
- `body`: Include discovery query, counts, next steps

Next workflow run will properly track created issues on the project board and post completion status.

Original prompt

Check campaign run: https://github.com/githubnext/gh-aw/actions/runs/21485194224
After create issue, agent should add this link to the project (In Progress via update-project) as this is part of the instructions and finally do project status update entry (part of campaign.md instructions as a step that should always be done at end).

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