Add GitBook page for the real-training implementation plan

[Copilot]

• Inspect the current branch state and baseline validation before syncing with main
• Confirm the repository is shallow and needs a proper fetch of origin/main before integration
• Fetch full history as needed and bring in the latest origin/main
• Merge main into the current branch and resolve/reapply changes only if necessary
• Re-run validation after the merge and review the resulting diff/status
• Run automated code review and security scan before finalizing

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