feat: initial Claude Code configuration scaffold

Comprehensive Claude Code guidance system with:

- 5 agents: tdd-guardian, code-reviewer, security-scanner, refactor-scan, dependency-audit
- 18 skills covering languages (Python, TypeScript, Rust, Go, Java, C#),
  infrastructure (AWS, Azure, GCP, Terraform, Ansible, Docker/K8s, Database, CI/CD),
  testing (TDD, UI, Browser), and patterns (Monorepo, API Design, Observability)
- 3 hooks: secret detection, auto-formatting, TDD git pre-commit
- Strict TDD enforcement with 80%+ coverage requirements
- Multi-model strategy: Opus for planning, Sonnet for execution (opusplan)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

.claude/hooks/check-secrets.sh

@@ -0,0 +1,51 @@
+#!/bin/bash
+# Check for secrets in files before writing
+# Exit code 2 blocks the operation in Claude Code
+
+set -e
+
+# Read the file path from stdin (Claude passes tool_input as JSON)
+INPUT=$(cat)
+FILE_PATH=$(echo "$INPUT" | jq -r '.file_path // .filePath // empty')
+
+if [ -z "$FILE_PATH" ]; then
+    exit 0
+fi
+
+# Skip non-code files
+case "$FILE_PATH" in
+    *.md|*.txt|*.json|*.yaml|*.yml|*.toml|*.lock|*.svg|*.png|*.jpg|*.gif)
+        exit 0
+        ;;
+esac
+
+# Patterns that indicate secrets
+SECRET_PATTERNS=(
+    'password\s*=\s*["\x27][^"\x27]+'
+    'api[_-]?key\s*=\s*["\x27][^"\x27]+'
+    'secret[_-]?key\s*=\s*["\x27][^"\x27]+'
+    'aws[_-]?access[_-]?key[_-]?id\s*=\s*["\x27][A-Z0-9]+'
+    'aws[_-]?secret[_-]?access[_-]?key\s*=\s*["\x27][^"\x27]+'
+    'private[_-]?key\s*=\s*["\x27][^"\x27]+'
+    'database[_-]?url\s*=\s*["\x27]postgres(ql)?://[^"\x27]+'
+    'mongodb(\+srv)?://[^"\x27\s]+'
+    'redis://[^"\x27\s]+'
+    'AKIA[0-9A-Z]{16}'
+    'ghp_[a-zA-Z0-9]{36}'
+    'sk-[a-zA-Z0-9]{48}'
+    'xox[baprs]-[0-9a-zA-Z-]+'
+)
+
+# Check if file exists and scan for secrets
+if [ -f "$FILE_PATH" ]; then
+    for pattern in "${SECRET_PATTERNS[@]}"; do
+        if grep -qiE "$pattern" "$FILE_PATH" 2>/dev/null; then
+            echo "BLOCKED: Potential secret detected in $FILE_PATH"
+            echo "Pattern matched: $pattern"
+            echo "Please use environment variables or secrets manager instead."
+            exit 2
+        fi
+    done
+fi
+
+exit 0