chore: publish 4.0.0-beta.3

[pacphi]

Why

4.0.0-beta.3 on the beta npm tag (master plan Decision 1). Commands folded; first dashboard half.

In scope

Cut, publish, release notes.

Out of scope

Other tags.

Acceptance criteria

• npx @pacphi/agentic-kit@4.0.0-beta.3 --version prints the version
• latest and next are unchanged
• Release notes say which hosts are supported, which are not yet, the release each is planned for (Hermes: v5), and that users who rely on them should stay on 4.0.0-alpha.61

Dependencies

Blocked by: #386, #355, #356, #357, #358, #359, #360, #361, #362, #363, #364, #365, #366, #367, #368, #257, #369

Blocks: #388

Plan

• Release: 4.0.0-beta.3
• Size: size:S · Workstream: ws:release
• Epic: chore: 4.0 release train (epic) #304
• Card: REL-B3 in the card inventory
• Sources: Master plan (docs(plans): v4 GA master plan, supersession ledger and v5 registers #290) Decisions 1 and 2

Verification

• npx @pacphi/agentic-kit@4.0.0-beta.3 --version