feat: introduce managed memory

[omeraplak]

PR Checklist

Please check if your PR fulfills the following requirements:

• The commit message follows our guidelines: https://voltagent.dev/docs/community/contributing/#commit-convention

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

[changeset-bot]

🦋 Changeset detected

Latest commit: 1fa754a

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 3 packages

Name	Type
@voltagent/postgres	Patch
@voltagent/voltagent-memory	Patch
@voltagent/core	Patch

Not sure what this means? Click here to learn what changesets are.

Click here if you're a maintainer who wants to add another changeset to this PR

[cloudflare-workers-and-pages]

Deploying voltagent with    Cloudflare Pages

Latest commit:	1fa754a
Status:	✅  Deploy successful!
Preview URL:	https://c32b5a84.voltagent.pages.dev
Branch Preview URL:	https://feat-add-managed-memory.voltagent.pages.dev

View logs