Enhance save-session with smart session tracking

[kuiwang02]

What this PR does / why we need it:

Enhances the save-session command with incremental save mode and smart session tracking, plus adds comprehensive documentation.

Key improvements:

• Smart session tracking: Automatically detects whether to create new session or update existing one based on conversation history
• Security enhancement: Mandatory sensitive information redaction (API keys, tokens, passwords, usernames, etc.)
• Documentation: New README.md for session plugin with usage patterns and examples

Why:
Current session save creates duplicate files easily and lacks topic separation. This enhancement makes session management more intelligent and user-friendly, especially for long multi-topic conversations.

Which issue(s) this PR fixes:

Fixes N/A

Special notes for your reviewer:

• Key areas to review: Phase 0 (session detection) and Phase 1.5 (security requirements)
• About "Read tool" and "Write tool" references: These refer to Claude Code's built-in file operation tools. The smart session tracking feature works by checking the conversation's tool call history (Read/Write operations on session-*.md files) to automatically determine whether to create a new
  session or update an existing one. This is why the implementation documentation uses terms like "Read tool history" and "Write tool history."

Checklist:

• Subject and description added to both, commit and PR.
• Relevant issues have been referenced.
• This change includes docs.

Generated-by: Claude Code

[openshift-ci]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: kuiwang02
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[kuiwang02]

@brandisher if you have time, could you please would like to review this command again? Thanks

if it is ok, could you please help merge it? Thanks

[enxebre]

needs rebase

[openshift-merge-robot]

PR needs rebase.

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