feat: Sub-System Decomposition in architect.specify and architect.init (Issue #43)

[kanfil]

Summary

Implements sub-system decomposition feature for the architect commands as requested in Issue #43.

Changes Made

• Phase 0: Sub-System Detection added to both architect.specify (greenfield) and architect.init (brownfield)
• Auto-detection of sub-systems from PRD domains or code structure
• Interactive confirmation - user confirms sub-system breakdown before proceeding
• --no-decompose flag to disable automatic decomposition
• Updated ADR template with Sub-System field and column

Implementation Details

File	Changes
templates/commands/architect.specify.md	Added Phase 0 with PRD domain analysis
templates/commands/architect.init.md	Added Phase 0 with code structure analysis
scripts/bash/setup-architecture.sh	Added detect_subsystems() and --no-decompose flag
scripts/powershell/setup-architecture.ps1	Mirrored bash changes
templates/adr-template.md	Added Sub-System field

Usage

# Auto-decompose (default - detects multiple domains/sub-systems)
specify "Large e-commerce platform with auth, payments, inventory"

# Disable decomposition
specify "Small project" --no-decompose
init --no-decompose

Related Issue

Closes #43

[github-actions]

📊 Eval Results

Overall: 7/25 tests passed (28%)

Metric	Value
✅ Passed	7
❌ Failed	18
📈 Pass Rate	28%
🪙 Total Tokens	83,220
💾 Cached Tokens	0

❌ Failed Tests

• Unknown (score: 0.89)
• Unknown (score: 0.83)
• Unknown (score: 0.83)
• Unknown (score: 0.80)
• Unknown (score: 0.83)
• Unknown (score: 0.80)
• Unknown (score: 0.78)
• Unknown (score: 0.83)
• Unknown (score: 0.80)
• Unknown (score: 0.88)
• Unknown (score: 0.83)
• Unknown (score: 0.77)
• Unknown (score: 0.71)
• Unknown (score: 0.89)
• Unknown (score: 0.83)
• Unknown (score: 0.83)
• Unknown (score: 0.80)
• Unknown (score: 0.80)

⚠️ Quality thresholds not met (target: 85%). Please review failures.