docs: add one-shot setup architecture

[onutc]

Summary\n- add a plain-English architecture doc for one-shot Spritz setup\n- define the target install/deploy contract from environment definition to first working message\n- capture the required validation, runtime, and operator workflow pieces without implementing them yet\n\n## Testing\n- npx -y @simpledoc/simpledoc check

[gitrank-connector]

👍 GitRank PR Analysis

Score: 5 points

Metric	Value
Component	Other (1× multiplier)
Severity	P3 - Low (5 base pts)
Final Score	5 × 1 = 5

Eligibility Checks

Check	Status
Issue/Bug Fix	❌
Fix Implementation	✅
PR Documented	✅
Tests	✅ (not required)
Lines Within Limit	✅

Impact Summary

This PR introduces a comprehensive 687-line architecture document that outlines the target design for simplified one-shot Spritz environment setup. It defines required architectural components, design principles, responsibility splits, and validation checklists to guide future implementation phases. While valuable for planning and alignment, it does not fix any existing bugs or implement new functionality.

Analysis Details

Component Classification: This PR adds architectural documentation for one-shot Spritz setup, which does not fit into any specific code component category. It is purely documentation and falls under 'Other' as miscellaneous/uncategorized changes.

Severity Justification: This is a P3 (Low) severity contribution. It is documentation that defines future architectural goals and design principles without implementing any actual functionality, fixing bugs, or addressing critical issues. Documentation improvements are typically low-priority scoring items.

Eligibility Notes: The PR is properly documented with a clear description and passes fix_implementation check since it delivers exactly what the title promises (architecture documentation). Tests are not required for documentation changes, as this is a design specification document rather than code that needs validation. No issue is referenced because this appears to be a proactive architectural planning document rather than a bug fix.

---

Analyzed by GitRank 🤖