Add Nika (AI workflow engine) to Automated Workflows

[ThibautMelen]

Description

Adds Nika to Automated Workflows: a single-binary workflow engine for AI (Rust, AGPL-3.0). Repeated agent work becomes a reviewable .nika.yaml DAG — statically checked (schema, permits, honest cost floor) before any token is spent, executed budget-capped with tamper-evident traces. Ships a read-only MCP oracle, a VS Code extension, and a GitHub Action that posts the plan on PRs.

Disclosure: I'm the author.

Checklist

• The entry is a tool that uses AI
• The entry is a developer-focused tool
• The description is unambiguous and clear
• The description matches the style of other entries

[github-actions]

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