feat(marketplace): command consolidation + 8 new plugins (v8.1.0 → v9.0.0) [BREAKING]

Phase 1b: Rename all ~94 commands across 12 plugins to /<noun> <action>
sub-command pattern. Git-flow consolidated from 8→5 commands (commit
variants absorbed into --push/--merge/--sync flags). Dispatch files,
name: frontmatter, and cross-reference updates for all plugins.

Phase 2: Design documents for 8 new plugins in docs/designs/.

Phase 3: Scaffold 8 new plugins — saas-api-platform, saas-db-migrate,
saas-react-platform, saas-test-pilot, data-seed, ops-release-manager,
ops-deploy-pipeline, debug-mcp. Each with plugin.json, commands, agents,
skills, README, and claude-md-integration. Marketplace grows from 12→20.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

plugins/saas-db-migrate/commands/db-migrate-rollback.md

@@ -0,0 +1,130 @@
+---
+name: db-migrate rollback
+description: Generate rollback migration for a previously applied migration
+agent: migration-planner
+---
+
+# /db-migrate rollback - Rollback Generator
+
+## Skills to Load
+
+- skills/rollback-patterns.md
+- skills/visual-header.md
+
+## Visual Output
+
+Display header: `DB-MIGRATE - Rollback`
+
+## Usage
+
+```
+/db-migrate rollback [<migration>] [--steps=<n>] [--dry-run]
+```
+
+**Arguments:**
+- `<migration>`: Specific migration to roll back to (exclusive — rolls back everything after it)
+- `--steps`: Number of migrations to roll back from current head (default: 1)
+- `--dry-run`: Show what would be rolled back without generating files
+
+## Prerequisites
+
+Run `/db-migrate setup` first. Target migrations must have rollback/downgrade operations defined.
+
+## Process
+
+### 1. Identify Rollback Target
+
+Determine which migrations to reverse:
+- If `<migration>` specified: roll back all migrations applied after it
+- If `--steps=N`: roll back the last N applied migrations
+- Default: roll back the single most recent migration
+
+### 2. Check Rollback Feasibility
+
+For each migration to roll back, verify:
+
+| Check | Result | Action |
+|-------|--------|--------|
+| Downgrade function exists | Yes | Proceed |
+| Downgrade function exists | No | FAIL: Cannot auto-rollback; manual intervention needed |
+| Migration contains DROP TABLE | N/A | WARN: Data cannot be restored by rollback |
+| Migration contains data changes | N/A | WARN: DML changes may not be fully reversible |
+| Later migrations depend on this | Yes | Must roll back dependents first |
+
+### 3. Generate Rollback
+
+Depending on the tool:
+
+**Alembic:**
+- Generate `alembic downgrade <target_revision>` command
+- Show the downgrade SQL that will execute
+- If downgrade function is incomplete, generate supplementary migration
+
+**Prisma:**
+- Generate rollback migration SQL based on diff
+- Create new migration directory with rollback operations
+
+**Raw SQL:**
+- Generate new numbered migration file with reverse operations
+- Include transaction wrapping and safety checks
+
+### 4. Data Recovery Plan
+
+If rolled-back migrations included destructive operations:
+- Recommend backup restoration for lost data
+- Suggest data export before rollback
+- Identify tables/columns that will be recreated empty
+
+### 5. Present Rollback Plan
+
+Show the complete rollback strategy with warnings.
+
+## Output Format
+
+```
++----------------------------------------------------------------------+
+|  DB-MIGRATE - Rollback                                               |
++----------------------------------------------------------------------+
+
+Mode: Roll back 2 steps
+Tool: Alembic
+
+ROLLBACK PLAN
+
+Step 1: Undo migration_008_add_status_to_orders
+  Operations:
+    [-] DROP CONSTRAINT valid_status
+    [-] DROP COLUMN orders.status
+  Data Impact: Column data will be lost (12,450 rows)
+  Reversible: Partially (column recreated empty on re-apply)
+
+Step 2: Undo migration_007_add_order_items
+  Operations:
+    [-] DROP TABLE order_items
+  Data Impact: Table and all data will be lost (3,200 rows)
+  Reversible: Partially (table recreated empty on re-apply)
+
+WARNINGS
+  [!] 2 operations will cause data loss
+  [!] Back up affected tables before proceeding
+
+COMMANDS TO EXECUTE
+  alembic downgrade -2
+  # Or: alembic downgrade migration_006_add_orders_table
+
+Generated Files:
+  (No new files — Alembic uses existing downgrade functions)
+
+RECOMMENDED PRE-ROLLBACK STEPS
+  1. pg_dump --table=order_items myapp > order_items_backup.sql
+  2. pg_dump --table=orders --column-inserts myapp > orders_status_backup.sql
+  3. Review downgrade SQL with /db-migrate plan --include-rollback
+```
+
+## Important Notes
+
+- Rollback does NOT execute migrations; it generates the plan and/or files
+- Always back up data before rolling back destructive migrations
+- Some migrations are irreversible (data-only changes without backup)
+- Use `--dry-run` to preview without creating any files
+- After rollback, verify application compatibility with the older schema