Improve overlay failure hints

[SilverSupplier]

Summary

• Improve overlay failure reasons for anchor position, scale mismatch, dependency failure, and detached seal proximity.
• Add structured overlay scale hints so the next-action copy stays aligned with operator-specific scale failures.
• Make martial_axis dependency feedback player-facing by referring to the prior cut decoration instead of internal operator names.
• Add EditMode and PlayMode coverage for overlay failure and success feedback paths.

Verification

• Unity EditMode tests: 20 passed
• Unity PlayMode tests: 9 passed
• node scripts/validate-doc-state.mjs
• GitHub build, test, validate-docs, and codeql checks

Notes

• This PR is scoped to overlay feedback and recognition-result copy for [Child #14] overlay anchor/dependency 실패 힌트 개선 #39.
• Base family failure copy and escalation coverage are handled separately in Improve base family failure hints #60 and Strengthen feedback escalation coverage #61.

Closes #39