#1378 feat: prepare VoltAgent 3 next prerelease

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Bugs / Features

• Related issue(s) linked
• Tests for the changes have been added
• Docs have been added / updated
• Changesets have been added https://voltagent.dev/docs/community/contributing/#creating-a-changeset

What is the current behavior?

What is the new behavior?

fixes (issue)

Notes for reviewers

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Summary by cubic

Prepares the VoltAgent 3 prerelease on the next channel with Node 22, zod@^4, and AI SDK v7-first tooling. @voltagent/core now exposes tool()/ToolSet, native AI SDK tool execution and streaming semantics, typed context schema validation, and per-provider-call retry/fallback. Adds an account-free local playground, refreshes examples and CI, and runs a new AI SDK compatibility matrix on Node 22/24.

Dependencies

• Enables Changesets prerelease mode (next) and Node.js 22 CI; adds dedicated AI SDK compatibility checks against SDK 7.0.0 and 7.
• Bumps @voltagent/* to 3.0.0-next.x, ai@^7, @ai-sdk/openai@^4, @ai-sdk/react@^4, @openrouter/ai-sdk-provider@^3, ollama-ai-provider-v2@^4, and zod@^4.
• Adds @voltagent/libsql working memory, aligned Hono ^4.9.1, re-exported AI SDK primitives/types from @voltagent/core, and the new @voltagent/playground package.
• Adds tool approval guidance (voltagent#1373) and standardizes package type/types order.

Migration

• Require Node.js 22 and zod@^4; install via @next/3.0.0-next.x.
• Tools: createTool -> tool, parameters -> inputSchema, configure tools as a ToolSet object map; raw AI SDK tools remain first-class and can be decorated with enhanceTool().
• Native tools preserve AI SDK semantics: thrown errors become tool-error, AsyncIterable returns stream results, and final-output validation requires voltagent.validateOutput: true.
• Native streaming requires a directly returned AsyncIterable; move async setup into an async generator. toUIMessageStreamResponse({ onEnd }) replaces onFinish.
• Usage fields: usage.outputTokenDetails.reasoningTokens and usage.inputTokenDetails.cacheReadTokens.
• generateObject: pass instructions instead of system; createTool remains for legacy compatibility. Optional playground starts on loopback port 3142 via playground: false or { enabled, port, apiUrl }.