Rename runnables into tasks (#8119)

Release Notes:

- N/A

crates/tasks_ui/src/oneshot_source.rs

@@ -0,0 +1,77 @@
+use std::sync::Arc;
+
+use gpui::{AppContext, Model};
+use task::{Source, SpawnInTerminal, Task, TaskId};
+use ui::Context;
+
+pub struct OneshotSource {
+    tasks: Vec<Arc<dyn Task>>,
+}
+
+#[derive(Clone)]
+struct OneshotTask {
+    id: TaskId,
+}
+
+impl OneshotTask {
+    fn new(prompt: String) -> Self {
+        Self { id: TaskId(prompt) }
+    }
+}
+
+impl Task for OneshotTask {
+    fn id(&self) -> &TaskId {
+        &self.id
+    }
+
+    fn name(&self) -> &str {
+        &self.id.0
+    }
+
+    fn cwd(&self) -> Option<&std::path::Path> {
+        None
+    }
+
+    fn exec(&self, cwd: Option<std::path::PathBuf>) -> Option<SpawnInTerminal> {
+        if self.id().0.is_empty() {
+            return None;
+        }
+        Some(SpawnInTerminal {
+            id: self.id().clone(),
+            label: self.name().to_owned(),
+            command: self.id().0.clone(),
+            args: vec![],
+            cwd,
+            env: Default::default(),
+            use_new_terminal: Default::default(),
+            allow_concurrent_runs: Default::default(),
+            separate_shell: true,
+        })
+    }
+}
+
+impl OneshotSource {
+    pub fn new(cx: &mut AppContext) -> Model<Box<dyn Source>> {
+        cx.new_model(|_| Box::new(Self { tasks: Vec::new() }) as Box<dyn Source>)
+    }
+
+    pub fn spawn(&mut self, prompt: String) -> Arc<dyn Task> {
+        let ret = Arc::new(OneshotTask::new(prompt));
+        self.tasks.push(ret.clone());
+        ret
+    }
+}
+
+impl Source for OneshotSource {
+    fn as_any(&mut self) -> &mut dyn std::any::Any {
+        self
+    }
+
+    fn tasks_for_path(
+        &mut self,
+        _path: Option<&std::path::Path>,
+        _cx: &mut gpui::ModelContext<Box<dyn Source>>,
+    ) -> Vec<Arc<dyn Task>> {
+        self.tasks.clone()
+    }
+}