Add guided Local Codex research investigations

[Techris93]

Summary

• add one primary Run Investigation Pipeline action to Research cases
• show durable step/job status with automatic refresh and checkpoint recovery
• present bounded, grouped, editable Accept/Reject proposals with explicit human gates
• add typed helper actions, responsive enterprise layout, preview fixture, and operator documentation

Verification

• 68 dashboard Python tests and 13 subtests passed
• JavaScript checks and console contract tests passed
• npm audit reports zero vulnerabilities
• desktop and mobile browser QA passed with no horizontal overflow
• Core dependency is merged in Automate research investigations with Local Codex secopsai#82

[cloudflare-workers-and-pages]

Deploying secopsai-dashboard with    Cloudflare Pages

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