docs: clarify Aqua repository prerequisites

[konojunya]

Summary

• Place Aqua configuration and policy at the Git repository root.
• Keep the first SVG walkthrough inside the configured project.
• Sync the canonical documentation pin.

Verification

• Published Aqua-installed CLI 0.5.1 passed all four localized first-render walkthroughs.
• Documentation generation, 20 tests, and source integrity checks passed upstream.
• No runtime or release artifact changes.