linear v2: Simple Mode (#7734)

A major, full rewrite of linear mode, now under the name "Simple Mode". 
- Fixes widget styling
- Adds a new simplified history
- Adds support for non-image outputs
- Supports right sidebar
- Allows and panning on the output image preview
- Provides support for drag and drop zones
- Moves workflow notes into a popover.
- Allows scrolling through outputs with Ctrl+scroll or arrow keys

The primary means of accessing Simple Mode is a toggle button on the
bottom right. This button is only shown if a feature flag is enabled, or
the user has already seen linear mode during the current session. Simple
Mode can also be accessed by
- Using the toggle linear mode keybind
- Loading a workflow that that was saved in Simple Mode workflow
- Loading a template url with appropriate parameter

<img width="1790" height="1387" alt="image"
src="https://github.com/user-attachments/assets/d86a4a41-dfbf-41e7-a6d9-146473005606"
/>

Known issues:
- Outputs on cloud are not filtered to those produced by the current
workflow.
  - Output filtering has been globally disabled for consistency
- Outputs will load more items on scroll, but does not unload
- Performance may be reduced on weak devices with very large histories.

┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-7734-linear-v2-2d16d73d3650819b8a10f150ff12ea22)
by [Unito](https://www.unito.io)

packages/design-system/src/css/style.css

@@ -247,6 +247,7 @@
   --inverted-background-hover: var(--color-charcoal-600);
   --warning-background: var(--color-gold-400);
   --warning-background-hover: var(--color-gold-500);
+  --success-background: var(--color-jade-600);
   --border-default: var(--color-smoke-600);
   --border-subtle: var(--color-smoke-400);
   --muted-background: var(--color-smoke-700);
@@ -372,6 +373,7 @@
   --inverted-background-hover: var(--color-smoke-200);
   --warning-background: var(--color-gold-600);
   --warning-background-hover: var(--color-gold-500);
+  --success-background: var(--color-jade-600);
   --border-default: var(--color-charcoal-200);
   --border-subtle: var(--color-charcoal-300);
   --muted-background: var(--color-charcoal-100);
@@ -516,6 +518,7 @@
   --color-inverted-background-hover: var(--inverted-background-hover);
   --color-warning-background: var(--warning-background);
   --color-warning-background-hover: var(--warning-background-hover);
+  --color-success-background: var(--success-background);
   --color-border-default: var(--border-default);
   --color-border-subtle: var(--border-subtle);
   --color-muted-background: var(--muted-background);