feat: add feature-dev skill with 7-phase workflow

Structured feature development with codeagent orchestration:
- Discovery, Exploration, Clarification, Architecture phases
- Implementation, Review, Summary phases
- Parallel agent execution via code-explorer, code-architect, etc.
- Hook-based workflow automation with validation scripts

Generated with SWE-Agent.ai

Co-Authored-By: SWE-Agent.ai <noreply@swe-agent.ai>

skills/feature-dev/scripts/setup-feature-dev.sh

@@ -0,0 +1,111 @@
+#!/usr/bin/env bash
+
+set -euo pipefail
+
+usage() {
+	cat <<'EOF'
+Usage: setup-feature-dev.sh [options] PROMPT...
+
+Creates (or overwrites) project state file:
+  .claude/feature-dev.local.md
+
+Options:
+  --max-phases N            Default: 7
+  --completion-promise STR  Default: <promise>FEATURE_COMPLETE</promise>
+  -h, --help                Show this help
+EOF
+}
+
+die() {
+	echo "❌ $*" >&2
+	exit 1
+}
+
+phase_name_for() {
+	case "${1:-}" in
+	1) echo "Discovery" ;;
+	2) echo "Exploration" ;;
+	3) echo "Clarification" ;;
+	4) echo "Architecture" ;;
+	5) echo "Implementation" ;;
+	6) echo "Review" ;;
+	7) echo "Summary" ;;
+	*) echo "Phase ${1:-unknown}" ;;
+	esac
+}
+
+max_phases=7
+completion_promise="<promise>FEATURE_COMPLETE</promise>"
+declare -a prompt_parts=()
+
+while [ $# -gt 0 ]; do
+	case "$1" in
+	-h|--help)
+		usage
+		exit 0
+		;;
+	--max-phases)
+		[ $# -ge 2 ] || die "--max-phases requires a value"
+		max_phases="$2"
+		shift 2
+		;;
+	--completion-promise)
+		[ $# -ge 2 ] || die "--completion-promise requires a value"
+		completion_promise="$2"
+		shift 2
+		;;
+	--)
+		shift
+		while [ $# -gt 0 ]; do
+			prompt_parts+=("$1")
+			shift
+		done
+		break
+		;;
+	-*)
+		die "Unknown argument: $1 (use --help)"
+		;;
+	*)
+		prompt_parts+=("$1")
+		shift
+		;;
+	esac
+done
+
+prompt="${prompt_parts[*]:-}"
+[ -n "$prompt" ] || die "PROMPT is required (use --help)"
+
+if ! [[ "$max_phases" =~ ^[0-9]+$ ]] || [ "$max_phases" -lt 1 ]; then
+	die "--max-phases must be a positive integer"
+fi
+
+project_dir="${CLAUDE_PROJECT_DIR:-$PWD}"
+state_dir="${project_dir}/.claude"
+state_file="${state_dir}/feature-dev.local.md"
+
+mkdir -p "$state_dir"
+
+phase_name="$(phase_name_for 1)"
+
+cat > "$state_file" << EOF
+---
+active: true
+current_phase: 1
+phase_name: "$phase_name"
+max_phases: $max_phases
+completion_promise: "$completion_promise"
+---
+
+# feature-dev loop state
+
+## Prompt
+$prompt
+
+## Notes
+- Update frontmatter current_phase/phase_name as you progress
+- When complete, include the frontmatter completion_promise in your final output
+EOF
+
+echo "Initialized: $state_file"
+echo "phase: 1/$max_phases ($phase_name)"
+echo "completion_promise: $completion_promise"