feat(ui): redesign context and compression UI for a more seamless experience

- Added ui.showContextWindowWarning setting (default false).
- Implemented forced auto-compression on context overflow when warning is disabled.
- Redesigned compression messages to be subtle (gray, no icon, left border).
- Removed automatic context usage percentage from the minimal/focus UI.
- Changed ui.hideContextSummary default to true.
- Updated and verified all relevant tests.

Note: Includes a behavioral change where the CLI now attempts to force-compress
history when the context window is full rather than blocking by default.

packages/cli/src/ui/commands/compressCommand.test.ts

@@ -39,6 +39,7 @@ describe('compressCommand', () => {
         originalTokenCount: null,
         newTokenCount: null,
         compressionStatus: null,
+        model: 'test-model',
       },
     };
     await compressCommand.action!(context, '');
@@ -70,6 +71,7 @@ describe('compressCommand', () => {
         compressionStatus: null,
         originalTokenCount: null,
         newTokenCount: null,
+        model: 'test-model',
       },
     });
 
@@ -86,6 +88,7 @@ describe('compressCommand', () => {
           compressionStatus: CompressionStatus.COMPRESSED,
           originalTokenCount: 200,
           newTokenCount: 100,
+          model: 'test-model',
         },
       },
       expect.any(Number),