# Phase 3 Step 1: Trello Write Operations

**Status:** Active
**Priority:** High
**Feature:** Interactive Dashboard (Write Ops)

## Description
Currently, the Trello client is read-only. We need to implement `CreateCard` and `UpdateCard` to enable interactivity (adding tasks, moving cards, completing items).

## Requirements
1.  **CreateCard:**
    *   Method: `POST /1/cards`
    *   Parameters: `name`, `idList`, `desc` (optional), `due` (optional).
    *   Returns: Created `models.Card`.

2.  **UpdateCard:**
    *   Method: `PUT /1/cards/{id}`
    *   Parameters: Flexible map of updates (e.g., `idList` to move, `closed=true` to archive).
    *   Returns: Updated `models.Card` (or just error).

## Reproduction / Test Plan
Since we cannot hit the real Trello API in tests, we will use `httptest.Server` to mock the API responses.

### `internal/api/trello_test.go`
```go
package api

import (
	"encoding/json"
	"net/http"
	"net/http/httptest"
	"testing"
	"time"

	"task-dashboard/internal/models"
)

func TestTrelloClient_CreateCard(t *testing.T) {
	// Mock Server
	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		if r.Method != "POST" {
			t.Errorf("Expected POST, got %s", r.Method)
		}
		if r.URL.Path != "/1/cards" {
			t.Errorf("Expected /1/cards, got %s", r.URL.Path)
		}
		
		// Verify params
		r.ParseForm()
		if r.Form.Get("name") != "New Task" {
			t.Errorf("Expected name='New Task', got %s", r.Form.Get("name"))
		}

		// Return mock response
		card := models.Card{
			ID:   "new-card-id",
			Name: "New Task",
		}
		json.NewEncoder(w).Encode(card)
	}))
	defer server.Close()

	client := &TrelloClient{
		BaseURL: server.URL,
		Key:     "test-key",
		Token:   "test-token",
		Client:  server.Client(),
	}

	card, err := client.CreateCard("list-id", "New Task", "Description", nil)
	if err != nil {
		t.Fatalf("CreateCard failed: %v", err)
	}
	if card.ID != "new-card-id" {
		t.Errorf("Expected ID 'new-card-id', got %s", card.ID)
	}
}
```