Upgrade to bubbletea v2, lipgloss v2, and bubbles v2 + fix CI Go version

[Copilot]

Migrates from github.com/charmbracelet/* v1 to charm.land/*/v2 per the bubbletea v2 upgrade guide. Also bumps the CI Go version to 1.25, required transitively by charm.land/lipgloss/v2.

Dependency changes

• github.com/charmbracelet/bubbletea → charm.land/bubbletea/v2 v2.0.2
• github.com/charmbracelet/lipgloss → charm.land/lipgloss/v2 v2.0.2
• github.com/charmbracelet/bubbles → charm.land/bubbles/v2 v2.0.0

bubbletea v2 API changes

• View() now returns tea.View via tea.NewView(...) instead of string
• Key events: tea.KeyMsg → tea.KeyPressMsg; field-based matching replaced with msg.String() and msg.Text

// Before
case tea.KeyMsg:
    switch msg.Type {
    case tea.KeyEnter:
    case tea.KeyRunes:
        for _, r := range msg.Runes { ... }
    }

// After
case tea.KeyPressMsg:
    switch msg.String() {
    case "enter":
    default:
        for _, r := range msg.Text { ... }
    }

bubbles v2 API changes

• progress.WithGradient(a, b) → progress.WithColors(lipgloss.Color(a), lipgloss.Color(b))
• Width setters changed from field assignment to methods: .Width = n → .SetWidth(n) (progress, help)
• progress.Update() no longer returns tea.Model — type assertion removed
• Table now requires explicit table.WithWidth() (viewport defaults to 0 in v2)
• Added s.Selected = s.Cell on unfocused tables — lipgloss v2 emits ANSI in test environments, previously causing alignment assertions to fail

lipgloss v2 API changes

• lipgloss.Color is now a function (func(string) color.Color), not a type — Theme struct fields changed to color.Color; messageFg != "" → messageFg != nil

CI

• Updated go-version in go.yml: 1.24 → 1.25 (charm.land/lipgloss/v2 requires Go 1.25)

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Upgrade to bubbletea v2</issue_title>
<issue_description>Upgrade as shown at https://github.com/charmbracelet/bubbletea/blob/main/UPGRADE_GUIDE_V2.md</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes Upgrade to bubbletea v2 #8

---

💬 Send tasks to Copilot coding agent from Slack and Teams to turn conversations into code. Copilot posts an update in your thread when it's finished.