feat: add release plan collaboration and versioned diffs

[huanghongbo-hhb]

Summary

• Add release plan collaboration state so users can see who is editing the same section.
• Generate one release plan version for each successful verb save and use version diff to show config changes in operation logs.
• Save section-level editable snapshots instead of full release plan or full workflow objects.

Why

• Users need clear change details for each release plan save.
• Multiple editors need real-time section-level collaboration hints.

Main Changes

• Add collaboration APIs and Redis-backed editing sessions for metadata, approval, and job:<jobID>.
• Attach version, section_key, section_name, and section_type to config logs.
• Save page-editable release plan snapshots, especially workflow input parameters, and diff them against the previous comparable version when viewing log details.
• Mask sensitive values and collapse large text fields in diff responses.
• Keep execute/retry/skip logs lightweight with status snapshots only.

Risk / Compatibility

• Existing verb + spec save requests remain unchanged.
• Each successful verb save creates one version; session_id is only used for collaboration state.
• Snapshots store editable config rather than full workflow objects, which keeps storage growth under control and aligns diff output with page inputs.

Test

• UAT verified update_name, update_approval, and update_release_job version/diff flows.
• UAT verified collaboration WebSocket join, heartbeat, leave, section grouping, and username display.
• go test ./pkg/microservice/aslan/core/release_plan/service

Contact

• Contact: huanghongbo@koderover.com

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