Fix consistency issues in visualizer + explorer scripts

- Move packages/visualizer → apps/visualizer (consistent with other apps)
- Fix explorer-seed.ts: import from packages/source-stripe/src/openapi
  instead of deleted packages/sync-engine
- Fix explorer-export.ts: output path apps/visualizer/public/explorer-data
- Fix EXPLORER_RUNBOOK.md + apps/visualizer/README.md: replace pnpm tsx
  with bun run, update packages/visualizer refs to apps/visualizer
- Add visualizer:with-data root script (explorer:build + visualizer)
- Add pg to root devDependencies so explorer scripts resolve it

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Committed-By-Agent: claude

Author: tonyxiao

packages/visualizer/.gitignore apps/visualizer/.gitignorepackages/visualizer/.gitignore renamed to apps/visualizer/.gitignore

@@ -5,12 +5,12 @@ This package contains the standalone browser UI for exploring generated Stripe s
 The visualizer has two parts:
 
 - `pnpm explorer:build` generates static artifacts.
-- `packages/visualizer` loads those artifacts into PGlite and lets you run SQL in the browser.
+- `apps/visualizer` loads those artifacts into PGlite and lets you run SQL in the browser.
 
 ## Generated artifacts
 
-- `packages/visualizer/public/explorer-data/bootstrap.sql`
-- `packages/visualizer/public/explorer-data/manifest.json`
+- `apps/visualizer/public/explorer-data/bootstrap.sql`
+- `apps/visualizer/public/explorer-data/manifest.json`
 
 These files are generated and should stay out of version control.
 
@@ -34,11 +34,11 @@ After hydration, all SQL runs locally in the browser against the generated Strip
 `pnpm explorer:build` is the normal command, but the underlying phase scripts still exist for debugging:
 
 ```bash
-pnpm tsx scripts/explorer-harness.ts start
-pnpm tsx scripts/explorer-migrate.ts --api-version=2020-08-27
-pnpm tsx scripts/explorer-seed.ts --api-version=2020-08-27 --seed=42
-pnpm tsx scripts/explorer-export.ts
-pnpm tsx scripts/explorer-harness.ts stop
+bun run scripts/explorer-harness.ts start
+bun run scripts/explorer-migrate.ts --api-version=2020-08-27
+bun run scripts/explorer-seed.ts --api-version=2020-08-27 --seed=42
+bun run scripts/explorer-export.ts
+bun run scripts/explorer-harness.ts stop
 ```
 
 ## Notes

packages/visualizer/README.md apps/visualizer/README.mdpackages/visualizer/README.md renamed to apps/visualizer/README.md

@@ -227,4 +227,4 @@
     "tablesWithData": 106,
     "emptyTables": []
   }
-}
+}