feat(fiction-assistance): register plugin with full bespoke command set

Snapshot of the fiction-assistance plugin in its original Universalis-
specific form before generalization. Adds the missing plugin.json
manifest (subdirectory command paths explicitly listed), moves the two
stray root-level review files into their proper homes (review-all.md
into the reviewing-fiction skill, review-final.md as a command with
frontmatter), and registers the plugin in the marketplace.

Preserved here so the original card-generation and vault-maintenance
commands remain recoverable when the plugin is reduced to a portable
guidance-and-analysis subset in the next commit.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

fiction-assistance/commands/review/strategic-review.md

@@ -0,0 +1,39 @@
+# Strategic Review Command
+
+**Description:** Provides actionable, craft-based literary criticism focused on fixable problems rather than subjective preferences.
+
+**Usage:** `/strategic-review [content to review]`
+
+**Agent:** line-editor (show the user the output of the agent)
+
+**Prompt:**
+```
+Re-read "$ARGUMENTS" with these specific craft lenses:
+
+1. **Narrative Economy**: Which scenes/passages serve multiple story functions vs single purposes? Where could content be combined or streamlined without losing essential atmosphere or emotional grounding?
+
+2. **Reader Engagement**: Where might reader attention flag? What creates the strongest engagement vs weakest? Consider both pacing AND reader investment/immersion.
+
+3. **Character Revelation**: Where do we learn about characters through action/dialogue vs exposition? Which methods are most effective?
+
+4. **Tension Management**: How does tension build and release throughout? Where could it be better managed?
+
+5. **Reader Experience Balance**: Identify passages that could be enhanced for both efficiency AND enjoyment. Avoid suggesting cuts that sacrifice atmosphere, emotional grounding, or reader orientation for mere speed.
+
+Provide actionable, specific feedback with scene and line references where possible. Focus on problems that have clear solutions rather than subjective preferences.
+
+**Structure your response as:**
+- Brief analysis for each of the 5 craft lenses
+- Specific scene and line number references for suggested improvements
+- Priority ranking of suggested changes (highest impact first)
+- Concrete revision suggestions where appropriate
+
+Avoid subjective style preferences. Focus on craft elements that demonstrably affect reader experience and story function. Remember: the goal is prose that's both engaging AND purposeful, not just fast. Consider whether suggested changes enhance or diminish reader investment and emotional immersion.
+```
+
+**Example Output:**
+- Multi-function scenes identified vs single-purpose areas
+- Specific scene and line ranges that could be tightened
+- Tension peaks/valleys with suggested improvements
+- Character revelation effectiveness analysis
+- Prioritized action items for revision