Add Creative Writing expansion pack (#414)

* Add Creative Writing expansion pack
- 10 specialized writing agents for fiction and narrative design
- 8 complete workflows (novel, screenplay, short story, series)
- 27 quality checklists for genre and technical validation
- 22 writing tasks covering full creative process
- 8 professional templates for structured writing
- KDP publishing integration support

* Fix bmad-creative-writing expansion pack formatting and structure

- Convert all agents to standard BMAD markdown format with embedded YAML
- Add missing core dependencies (create-doc, advanced-elicitation, execute-checklist)
- Add bmad-kb.md customized for creative writing context
- Fix agent dependency references to only include existing files
- Standardize agent command syntax and activation instructions
- Clean up agent dependencies for beta-reader, dialog-specialist, editor, genre-specialist, narrative-designer, and world-builder

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Co-authored-by: Brian <bmadcode@gmail.com>

expansion-packs/bmad-creative-writing/workflows/novel-serial-workflow.yaml

@@ -0,0 +1,51 @@
+---
+workflow:
+  id: novel-serial-workflow
+  name: Iterative Release Novel Workflow
+  description: >-
+    Web‑serial cycle with regular releases, reader feedback, and season‑end
+    professional critique.
+  phases:
+    sprint-planning:
+      - agent: plot-architect
+        task: select-next-arc
+        output: release-plan.md
+    chapter-loop:
+      - agent: editor
+        task: create-draft-section
+        input: release-plan.md
+        repeat: per-chapter
+        output: chapter-draft.md
+      - agent: dialog-specialist
+        task: workshop-dialog
+        input: chapter-draft.md
+        output: chapter-dialog.md
+      - agent: beta-reader
+        task: quick-feedback
+        input: chapter-dialog.md
+        output: chapter-notes.md
+      - agent: editor
+        task: final-polish
+        input:
+          - chapter-dialog.md
+          - chapter-notes.md
+        output: chapter-final.md
+      - agent: editor
+        task: publish-chapter
+        input: chapter-final.md
+        output: publication-log.md
+    retrospective:
+      - agent: beta-reader
+        task: analyze-reader-feedback
+        input: publication-log.md
+        output: retro.md
+    season-critique:
+      - agent: book-critic
+        task: critical-review
+        input: publication-log.md
+        output: critic-review.md
+  completion_criteria:
+    - publication-log.md exists
+    - critic-review.md exists
+...
+