refactor: formulas use JSON instead of YAML (gt-8tmz)

JSON for consistency with beads (issues.jsonl, molecules.jsonl).
Agents create/manage formulas; humans use visualizers.

- Simpler parsing (Go built-in JSON)
- No YAML gotchas
- Agents generate JSON flawlessly

.beads/formulas/shiny.formula.yaml

@@ -1,67 +0,0 @@
-# shiny.formula.yaml
-# Engineer in a Box - the canonical right way to do engineering
-# Named for Mad Max: "Shiny and chrome!"
-
-formula: shiny
-description: |
-  The canonical engineering workflow. Design before you code.
-  Review before you ship. Test before you submit.
-
-  This is what "doing it right" looks like.
-version: 1
-
-vars:
-  feature: "{{feature}}"           # What you're building
-  assignee: "{{assignee}}"         # Who's doing the work
-
-steps:
-  - id: design
-    description: |
-      Think carefully about architecture before writing code.
-
-      Consider:
-      - How does this fit into the existing system?
-      - What are the edge cases?
-      - What could go wrong?
-      - Is there a simpler approach?
-
-      Output a brief design doc or notes.
-
-  - id: implement
-    description: |
-      Write the code for {{feature}}.
-
-      Follow the design. Keep it simple. Don't gold-plate.
-      Write code that's easy to review.
-    needs: [design]
-
-  - id: review
-    description: |
-      Review the implementation.
-
-      Check for:
-      - Does it match the design?
-      - Are there obvious bugs?
-      - Is it readable and maintainable?
-      - Are there security concerns?
-    needs: [implement]
-
-  - id: test
-    description: |
-      Write and run tests.
-
-      - Unit tests for new code
-      - Integration tests if needed
-      - Run the full test suite
-      - Fix any regressions
-    needs: [review]
-
-  - id: submit
-    description: |
-      Submit for merge.
-
-      - Final check: git status, git diff
-      - Commit with clear message
-      - Push and create PR (or merge directly if crew)
-      - Notify relevant parties
-    needs: [test]