feat: Add openspec-sync-specs and openspec-verify-change skills

- Introduced `openspec-sync-specs` skill to sync delta specs to main specs, allowing intelligent merging of requirements.
- Added `openspec-verify-change` skill to verify implementation against change artifacts, ensuring completeness, correctness, and coherence before archiving.

docs: Create CLAUDE.md for project guidance

- Added CLAUDE.md to provide an overview of the PCLI project, including build, test commands, architecture, and resource addition guidelines.

chore: Add new change and design documents for project filter in status command

- Created `.openspec.yaml`, `design.md`, `proposal.md`, and `tasks.md` for the `add-project-filter-to-status` change.
- Updated specs for CLI commands and status command to include project filtering functionality.

feat: Expand board included parsing in API client

- Added parsing for `labels`, `cardLabels`, and `cardMemberships` in the `GetBoard` response.
- Updated `ListCardsByBoard` to enrich card output with label names, enhancing usability in kanban sync workflows.

CLAUDE.md

@@ -0,0 +1,58 @@
+# CLAUDE.md
+
+This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
+
+## Project Overview
+
+PCLI is a Go CLI tool for interacting with the Planka (v2.0) project management API. It uses the Cobra framework with minimal dependencies (only Cobra + standard library).
+
+## Build & Test Commands
+
+```bash
+go build -o pcli .                # Build for development
+./build.sh                        # Multi-platform release build (linux/darwin/windows)
+./test.sh                         # Integration tests (requires live Planka instance)
+```
+
+Integration tests require `PLANKA_URL` and `PLANKA_API_KEY` environment variables pointing to a running Planka instance.
+
+There is no unit test suite or linter configured — tests are shell-based integration tests in `test.sh`.
+
+## Architecture
+
+**Entry point**: `main.go` → `cmd.Execute()`
+
+**Package layout**:
+- `cmd/` — Cobra command definitions, one file per resource (project.go, board.go, card.go, etc.)
+- `client/` — HTTP API client, one file per resource matching cmd/ structure
+- `model/types.go` — All domain types (Project, Board, Card, List, Label, Task, Comment, etc.)
+- `output/output.go` — Dual-format output: JSON envelope (`{data, error}`) or human-readable table via tabwriter
+- `logging/logging.go` — slog-based structured JSON logging to stderr
+
+**Command hierarchy**: `pcli <resource> <action>` (e.g., `pcli card create --list <id> --name "task"`)
+
+**Key patterns**:
+- Global flags (`--format`, `--url`, `--api-key`, `--log-level`) set in `cmd/root.go` PersistentPreRunE, which validates config and initializes the API client
+- Client methods follow `List*/Get*/Create*/Update*/Delete*` naming
+- API responses use typed structs with included relationships (e.g., board responses include lists and cards)
+- `friendlyAPIError()` in `cmd/errors.go` translates HTTP status codes to contextual messages
+- `DoWithFallback` in client supports trying alternate API endpoint patterns
+- Output uses reflection-based table rendering per type
+
+**Configuration**: Environment variables `PLANKA_URL` and `PLANKA_API_KEY`, overridable via CLI flags.
+
+## Adding a New Resource
+
+1. Define model structs in `model/types.go`
+2. Add client methods in `client/<resource>.go`
+3. Add command definitions in `cmd/<resource>.go` with subcommands (list, get, create, update, delete)
+4. Wire the parent command into `root.go` init()
+
+## Planka Sync
+
+**IMPORTANT**
+After completing any opsx workflow (/opsx:new, /opsx:ff, /opsx:continue,
+/opsx:apply, /opsx:verify, /opsx:archive, /opsx:bulk-archive), automatically
+reconcile Planka board state by running `/kanban-sync`.
+If the sync fails, log a brief warning and continue. Never block or retry —
+Planka sync is best-effort.