Add daily side-quest workflow and route it through the workshop orchestrator

[Copilot]

Adds a new daily agentic workflow, side-quest, that turns embedded primers inside large workshop steps into standalone optional adventures. Updates the workshop orchestrator so this workflow is scheduled, eligible for dispatch, and prioritized as part of the existing automation loop.

• New side-quest workflow

  • Adds .github/workflows/side-quest.md
  • Scans workshop/*.md for large candidate files that likely contain embedded mini tutorials
  • Instructs the agent to extract exactly one focused primer into workshop/side-quest-<topic>.md
  • Requires routing updates in the source step and workshop/README.md so the detour is optional and returns cleanly to the main path

• Routing and authoring constraints

  • Limits edits to workshop markdown files
  • Requires a single focused PR per run
  • Uses dedicated side-quest labels/prefixes and blocks duplicate open PRs via skip-if-match
  • Includes workflow-snippet validation guidance for extracted content that contains frontmatter examples

• Orchestrator integration

  • Adds side-quest to workshop-builder dispatchable workflows
  • Makes it a first-class candidate in Tier A selection
  • Adds explicit eligibility criteria and PR-blocking rules for open side-quest work
  • Extends focus routing so prompts like “side quest” or “tutorial” bias dispatch toward the new workflow

Example of the new orchestrator routing:

safe-outputs:
  dispatch-workflow:
    workflows:
      - workshop-author
      - workshop-order-review
      - side-quest
      - workshop-skill-activity-author
      - workshop-student-simulator
      - workshop-sync-check