## Why

There is no quick way to get an overview of the state of all boards in Planka from the CLI. Users currently need to run multiple commands (`board list`, then `board get` per board, then mentally tally cards) to understand what's where. A single `pcli status` command provides an at-a-glance summary — similar in spirit to `git status`.

## What Changes

- Add a new top-level `pcli status` command that:
  - Lists the total number of boards
  - For each board, displays a table of its lists with card counts
  - Card counts show open cards as the primary number, with closed cards in parentheses (e.g., `12 (2 closed)`)
  - Empty lists are shown with `0` cards
- Respects the global `--format` flag: JSON by default, table when `--format table` is specified
- Uses existing `ListBoards` and `GetBoard` client methods — no new API endpoints needed
- Sequential board fetching (one `GetBoard` call per board)

## Capabilities

### New Capabilities
- `status-command`: The top-level `pcli status` command, its data aggregation logic, and its output formatting (both JSON and table)

### Modified Capabilities
- `cli-commands`: Adding the new `status` top-level command to the CLI command tree

## Impact

- **New file**: `cmd/status.go` — command definition and aggregation logic
- **Modified file**: `output/output.go` — table rendering for the status summary type
- **Modified file**: `model/types.go` — new types for the status summary data structure
- No new dependencies required
- No breaking changes