Initial commit: Azure DevOps TUI client

A terminal-based user interface for browsing and managing Azure DevOps
work items. Features include:

- Browse work items with filtering by area, iteration, state, and type
- View work item details with markdown rendering
- Open work items in browser
- Create git branches from work items
- Update work item state
- Keyboard-driven navigation

🤖 Generated with [Claude Code](https://claude.ai/claude-code)

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

internal/models/iteration.go

@@ -0,0 +1,37 @@
+package models
+
+import "time"
+
+// Iteration represents an Azure DevOps iteration (sprint)
+type Iteration struct {
+	ID            string    `json:"id"`
+	Name          string    `json:"name"`
+	Path          string    `json:"path"`
+	StartDate     time.Time `json:"startDate"`
+	FinishDate    time.Time `json:"finishDate"`
+	TimeFrame     string    `json:"timeFrame"` // "past", "current", "future"
+	URL           string    `json:"url"`
+}
+
+// IsCurrent returns true if this is the current iteration
+func (i *Iteration) IsCurrent() bool {
+	return i.TimeFrame == "current"
+}
+
+// IsPast returns true if this iteration is in the past
+func (i *Iteration) IsPast() bool {
+	return i.TimeFrame == "past"
+}
+
+// IsFuture returns true if this iteration is in the future
+func (i *Iteration) IsFuture() bool {
+	return i.TimeFrame == "future"
+}
+
+// DisplayName returns a formatted name for display
+func (i *Iteration) DisplayName() string {
+	if i.IsCurrent() {
+		return i.Name + " (current)"
+	}
+	return i.Name
+}