docs: Add migration guide for v0.2.0 to v1.0.0

[lykinsbd]

Overview

Create a comprehensive migration guide to help users upgrade from v0.2.0 to v1.0.0.

Breaking Changes to Document

1. CLI Flag Renames (Kong Migration)

Old (v0.2.0):

./cisshgo -startingPort 10000 -transcriptMap custom.yaml

New (v1.0.0):

./cisshgo --starting-port 10000 --transcript-map custom.yaml

2. Transcript Map YAML Schema

Old (v0.2.0):

platforms:
  - csr1000v:
      vendor: "cisco"
      ...

New (v1.0.0):

platforms:
  csr1000v:
    vendor: "cisco"
    ...

Deliverables

• Create docs/migration-v0.2-to-v1.0.md
• Document both breaking changes with examples
• Provide step-by-step upgrade instructions
• Link to migration script (issue #TBD)
• Add to mkdocs.yml navigation

Content Structure

1. Overview of breaking changes
2. CLI flag migration with examples
3. Transcript map schema migration with examples
4. New features summary
5. Step-by-step upgrade checklist
6. Troubleshooting common issues

Related

• Depends on #TBD (migration script)
• Part of v1.0.0 release preparation