docs(actors): update JSDoc for actors SDK module

[abrahams-wix]

Summary

• Rewrites JSDoc across actors.types.ts to align with established terminology and writing style
• Replaces internal implementation-focused comments with developer-facing descriptions
• Adds full @param, @returns, and @example coverage on all public methods
• Aligns terminology with the Actors overview and reference docs: session vs instance, client vs page, incoming/outgoing message direction

🤖 Generated with Claude Code

[github-actions]

🚀 Package Preview Available!

---

Install this PR's preview build with npm:

npm i @base44-preview/sdk@0.8.48-pr.289.b9ea964

Prefer not to change any import paths? Install using npm alias so your code still imports @base44/sdk:

npm i "@base44/sdk@npm:@base44-preview/sdk@0.8.48-pr.289.b9ea964"

Or add it to your package.json dependencies:

{
  "dependencies": {
    "@base44/sdk": "npm:@base44-preview/sdk@0.8.48-pr.289.b9ea964"
  }
}

• 📦 Preview Package: @base44-preview/sdk@0.8.48-pr.289.b9ea964
• 🔗 View this commit on GitHub

---

_{Preview published to npm registry — try new features instantly!}