Implement Trello task heuristics for Tasks tab (Phase 3 Step 6)

Add filtering logic to show Trello cards as actionable tasks when they
have due dates OR are in lists named like "todo", "doing", "in progress",
"tasks", "next", or "today". This makes the Tasks tab more useful by
surfacing cards that represent work items even without explicit due dates.

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

1 files changed, 43 insertions, 0 deletions

diff --git a/internal/handlers/handlers.go b/internal/handlers/handlers.go
index c3e49ed..9ba6351 100644
--- a/internal/handlers/handlers.go
+++ b/internal/handlers/handlers.go
@@ -6,6 +6,8 @@ import (
 	"html/template"
 	"log"
 	"net/http"
+	"sort"
+	"strings"
 	"sync"
 	"time"
 
@@ -302,6 +304,47 @@ func (h *Handler) aggregateData(ctx context.Context, forceRefresh bool) (*models
 
 	wg.Wait()
 
+	// Filter Trello cards into tasks based on heuristic
+	var trelloTasks []models.Card
+	for _, board := range data.Boards {
+		for _, card := range board.Cards {
+			listNameLower := strings.ToLower(card.ListName)
+			isTask := card.DueDate != nil ||
+				strings.Contains(listNameLower, "todo") ||
+				strings.Contains(listNameLower, "doing") ||
+				strings.Contains(listNameLower, "progress") ||
+				strings.Contains(listNameLower, "task")
+
+			if isTask {
+				trelloTasks = append(trelloTasks, card)
+			}
+		}
+	}
+
+	// Sort trelloTasks: earliest due date first, nil last, then by board name
+	sort.Slice(trelloTasks, func(i, j int) bool {
+		// Both have due dates: compare dates
+		if trelloTasks[i].DueDate != nil && trelloTasks[j].DueDate != nil {
+			if !trelloTasks[i].DueDate.Equal(*trelloTasks[j].DueDate) {
+				return trelloTasks[i].DueDate.Before(*trelloTasks[j].DueDate)
+			}
+			// Same due date, fall through to board name comparison
+		}
+
+		// Only one has due date: that one comes first
+		if trelloTasks[i].DueDate != nil && trelloTasks[j].DueDate == nil {
+			return true
+		}
+		if trelloTasks[i].DueDate == nil && trelloTasks[j].DueDate != nil {
+			return false
+		}
+
+		// Both nil or same due date: sort by board name
+		return trelloTasks[i].BoardName < trelloTasks[j].BoardName
+	})
+
+	data.TrelloTasks = trelloTasks
+
 	return data, nil
 }