fix: resolve query provider, prisma template helper, and tailwind flag compatibility

[tannerlinsley]

Summary

• restore a default TanStack Query provider export for generated React query integrations (including tRPC + query), while caching context so router/provider share the same queryClient
• expose getPackageManagerExecuteScript in package.json EJS template rendering so Prisma template scripts render correctly again
• reintroduce --tailwind / --no-tailwind as compatibility flags that are accepted but loudly warned and ignored (Tailwind remains always-on)
• update CLI docs and alias README examples to match current Tailwind behavior

Validation

• pnpm --filter @tanstack/create test
• pnpm --filter @tanstack/cli test
• smoke scaffold/build: tanstack-query app (install + build)
• smoke scaffold/build: tanstack-query,tRPC app (install + build; verifies provider export fix)
• smoke scaffold: reported Prisma add-on combination from Error processing package.json.ejs for add-on prisma: ReferenceError: ejs:14 #374 now completes scaffolding without EJS ReferenceError
• smoke scaffold/build: app created with --no-tailwind scaffolds and builds successfully with warning output

Fixes #372
Fixes #374
Fixes #375