feat: merge behavior-driven-testing into test pillar

[robotlearning123]

Summary

• Integrate full BDT (behavior-driven-testing) methodology into agent-ready's test pillar
• Migrate all 6 reference files from agent-next/behavior-driven-testing repo
• Enhance SKILL.md, pillars.md, scoring-rubric.md with BDT content

What changed

SKILL.md — new "Testing Methodology (Behavior-Driven Testing)" section:

• Core principles, workflow overview
• Must-test branches quick reference table
• Branch matrix template
• Common mistakes, pre-release checklist
• Links to 6 detailed reference files

pillars.md — test pillar enhanced:

• Branch matrix at L4, full BDT methodology at L5
• BDT quick reference for P0/P1 branches

scoring-rubric.md — test pillar scoring updated:

• L4: systematic branch coverage
• L5: branch matrix tracked, all P0/P1 covered
• New "BDT methodology indicators" section

references/testing/ — 6 files migrated from behavior-driven-testing:

• analysis-phase.md (5.4KB)
• branch-matrices.md (4.1KB)
• design-phase.md (2.9KB)
• execution-phase.md (3.6KB)
• test-templates.md (12KB)
• testing-principles.md (20KB)

Follow-up

• Archive agent-next/behavior-driven-testing repo
• Update behavior-driven-testing README to redirect here

Test plan

• Verify SKILL.md renders correctly on GitHub
• Verify reference links resolve from SKILL.md
• Run agent-ready skill in Claude Code and confirm BDT section loads

🤖 Generated with Claude Code

[github-actions]

Agent Ready Scan Results

Metric	Value
Level	L1
Score	56%
Project Type	cli
Passed	true

Full Report

Agent Readiness Report

Level: L1
Score: 56%
Project Type: cli

Pillar Summary

• docs: L3 (53%)
• style: L5 (100%)
• build: L5 (89%)
• test: L4 (50%)
• security: L5 (67%)
• observability: L5 (100%)
• env: L5 (100%)
• task_discovery: L5 (67%)
• product: L5 (100%)
• agent_config: L1 (36%)
• code_quality: L2 (0%)

Failed Checks

• [L1] agent_config.gitignore_agent: File exists but does not contain required pattern: .gitignore
• [L2] agent_config.claude_commands: Found 0 files matching '.claude/commands/*.md', need at least 1
• [L2] agent_config.cursorrules: Only 0/2 alternatives passed (need 1)
• [L2] agent_config.aider_config: Only 0/3 alternatives passed (need 1)
• [L2] agent_config.copilot_config: Only 0/2 alternatives passed (need 1)
• [L2] agent_config.windsurf_rules: File not found: .windsurfrules
• [L3] agent_config.mcp_json: Only 0/2 alternatives passed (need 1)
• [L3] agent_config.claude_hooks: Found 0 files matching '.claude/hooks/*', need at least 1
• [L4] agent_config.multi_agent_support: Only 0/3 alternatives passed (need 1)
• [L4] agent_config.context_injection: Only 0/3 alternatives passed (need 1)

...and 22 more

[robotlearning123]

Code review

No issues found. Checked for bugs and CLAUDE.md compliance.

Note: Several minor issues were identified (level labeling consistency between pillars.md and scoring-rubric.md, untranslated Chinese text in testing-principles.md, missing L04 test template, M-series ID mismatch in test-templates.md) but none scored above the confidence threshold for flagging. These are worth addressing in a follow-up but do not block this PR.

🤖 Generated with Claude Code

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