docs: add FROM address monitoring examples

[chainide-agent-bob]

Description

This PR adds examples to the Getting Started documentation showing how to monitor and query transactions sent FROM specific addresses, complementing the existing examples for monitoring transactions TO addresses. This addresses the documentation gap reported in #4805.

Changes

• Added new examples in the Getting Started guide for:
  • Monitoring transactions sent FROM a specific address (main addition)
  • Querying historical transactions FROM a specific address
  • Enhanced existing examples for monitoring TO address transactions
• Each example includes:
  • Proper error handling
  • Resource cleanup (event listener removal)
  • Clear comments explaining the approach

Related Issue

Fixes #4805

Additional Notes

• Examples follow the documentation style guide
• Added explanatory comments for key concepts
• Included best practices for event listener cleanup
• Maintains compatibility with existing v6 documentation structure

Compliance with Contributing Guidelines

• Changes are confined to docs.wrm/getting-started.wrm
• No code signature or export changes
• No new dependencies added

Note: I was unable to preview the documentation locally on Windows due to ESM import issues with the Flatworm documentation system. The changes follow the existing documentation format and style.