feat: implement project management and media track handling

- Added domain entities for audio, subtitle, and video tracks.
- Created a Project entity to manage media editing sessions.
- Implemented value objects for file paths, sync offsets, track IDs, and languages.
- Developed infrastructure for asynchronous FFmpeg process execution.
- Built a user interface for selecting video files, adding audio and subtitle tracks, and managing output settings.
- Integrated error handling and logging for media processing tasks.

src/ui/components/execution_panel.rs

@@ -0,0 +1,93 @@
+use eframe::egui;
+
+/// Estado da execução do FFmpeg.
+#[derive(Default, PartialEq)]
+pub enum ExecutionState {
+    #[default]
+    Idle,
+    Running,
+    Success,
+    Error(String),
+}
+
+/// Painel de execução: botão "Gerar MKV", progresso e erros.
+pub struct ExecutionPanel {
+    pub state: ExecutionState,
+    pub log_lines: Vec<String>,
+}
+
+impl ExecutionPanel {
+    pub fn new() -> Self {
+        ExecutionPanel {
+            state: ExecutionState::Idle,
+            log_lines: Vec::new(),
+        }
+    }
+
+    pub fn add_log(&mut self, line: String) {
+        self.log_lines.push(line);
+        // Limita o histórico de log
+        if self.log_lines.len() > 200 {
+            self.log_lines.remove(0);
+        }
+    }
+
+    /// Renderiza o painel. Retorna `true` se o botão "Gerar MKV" foi clicado.
+    pub fn ui(&mut self, ui: &mut egui::Ui, can_generate: bool) -> bool {
+        let mut clicked = false;
+
+        ui.group(|ui| {
+            ui.heading("Gerar arquivo");
+
+            let is_running = self.state == ExecutionState::Running;
+
+            if ui
+                .add_enabled(
+                    can_generate && !is_running,
+                    egui::Button::new(if is_running {
+                        "Processando…"
+                    } else {
+                        "Gerar MKV"
+                    }),
+                )
+                .clicked()
+            {
+                clicked = true;
+            }
+
+            match &self.state {
+                ExecutionState::Idle => {}
+                ExecutionState::Running => {
+                    ui.spinner();
+                    ui.label("Processando...");
+                }
+                ExecutionState::Success => {
+                    ui.colored_label(egui::Color32::GREEN, "✓ Arquivo gerado com sucesso!");
+                }
+                ExecutionState::Error(msg) => {
+                    ui.colored_label(egui::Color32::RED, "✗ Erro durante o processamento:");
+                    ui.add(
+                        egui::TextEdit::multiline(&mut msg.as_str())
+                            .desired_rows(4)
+                            .desired_width(f32::INFINITY),
+                    );
+                }
+            }
+
+            // Log de progresso
+            if !self.log_lines.is_empty() {
+                ui.collapsing("Log detalhado", |ui| {
+                    egui::ScrollArea::vertical()
+                        .max_height(150.0)
+                        .show(ui, |ui| {
+                            for line in &self.log_lines {
+                                ui.label(egui::RichText::new(line).monospace().size(11.0));
+                            }
+                        });
+                });
+            }
+        });
+
+        clicked
+    }
+}