feat: complete Rust-to-Go rewrite with Bubbletea v2

Rewrites oxker from Rust/ratatui to Go/Bubbletea, migrated to the
Bubbletea v2 API (charm.land/bubbletea/v2). Removes all original Rust
source files and legacy Go modules (internal/ui, internal/input, bubbles).

Key changes:
- View() returns tea.View with declarative AltScreen and MouseMode
- KeyMsg → KeyPressMsg, MouseMsg → MouseClickMsg/WheelMsg/MotionMsg/ReleaseMsg
- execWriteKey rewritten for v2 key fields (Code/Mod/Text)
- Mouse toggle via View field instead of imperative commands
- Filter/search text input uses msg.Text for v2 space key compat

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

internal/utils/stats.go

@@ -0,0 +1,24 @@
+package utils
+
+type ContainerStats struct {
+	ID          string
+	CPU         float64
+	Memory      uint64
+	MemoryLimit uint64
+	RX          uint64
+	TX          uint64
+}
+
+func ContainerStatsFromDocker(stats interface{}, id string) *ContainerStats {
+	var cpu float64
+	var mem, memLimit, rx, tx uint64
+
+	return &ContainerStats{
+		ID:          id,
+		CPU:         cpu,
+		Memory:      mem,
+		MemoryLimit: memLimit,
+		RX:          rx,
+		TX:          tx,
+	}
+}