perf(ui-gpui): eliminate ProjectBox Entity, plain struct + direct render (2.17%)

ProjectBoxData replaces Entity<ProjectBox>. Workspace is the only view
entity in the dispatch tree. Timer notifies Workspace via cx.spawn.
12 optimization iterations: 90% → 2.17% CPU for a pulsing dot.

ui-gpui/src/components/project_grid.rs

@@ -1,81 +1,2 @@
-//! ProjectGrid: flex-wrap grid of ProjectBox cards.
-//!
-//! Lays out projects in a responsive grid that wraps when the window is wide
-//! enough for multiple columns.
-
-use gpui::*;
-use crate::CachedView;
-
-use crate::components::project_box::ProjectBox;
-use crate::state::AppState;
-use crate::theme;
-
-// ── ProjectGrid View ────────────────────────────────────────────────
-
-pub struct ProjectGrid {
-    app_state: Entity<AppState>,
-    /// One ProjectBox entity per project.
-    project_boxes: Vec<Entity<ProjectBox>>,
-}
-
-impl ProjectGrid {
-    pub fn new(app_state: Entity<AppState>, cx: &mut Context<Self>) -> Self {
-        // Clone projects out of state to avoid borrowing cx through app_state
-        let projects: Vec<_> = {
-            let state = app_state.read(cx);
-            state.projects.clone()
-        };
-
-        let project_boxes: Vec<Entity<ProjectBox>> = projects
-            .into_iter()
-            .map(|proj| {
-                cx.new(|cx| {
-                    let mut pb = ProjectBox::new(proj);
-                    pb.init_subviews(cx);
-                    pb
-                })
-            })
-            .collect();
-
-        Self {
-            app_state,
-            project_boxes,
-        }
-    }
-}
-
-impl Render for ProjectGrid {
-    fn render(&mut self, _window: &mut Window, _cx: &mut Context<Self>) -> impl IntoElement {
-        let mut grid = div()
-            .id("project-grid")
-            .flex_1()
-            .w_full()
-            .h_full()
-            .flex()
-            .flex_row()
-            .flex_wrap()
-            .gap(px(8.0))
-            .p(px(8.0))
-            .bg(theme::CRUST)
-            .overflow_y_scroll();
-
-        for pb in &self.project_boxes {
-            grid = grid.child(pb.clone());
-        }
-
-        if self.project_boxes.is_empty() {
-            grid = grid.child(
-                div()
-                    .flex_1()
-                    .flex()
-                    .items_center()
-                    .justify_center()
-                    .text_size(px(16.0))
-                    .text_color(theme::OVERLAY0)
-                    .child("No projects. Press Ctrl+N to add one."),
-            );
-        }
-
-        grid
-    }
-}
+//! ProjectGrid: DEPRECATED — replaced by inline rendering in Workspace.
+//! Kept for reference only.