fix(frontend): improve CoPilot chat table styling (#12094)

## Summary
- Remove left and right borders from tables rendered in CoPilot chat
- Increase cell padding (py-3 → py-3.5) for better spacing between text
and lines
- Applies to both Streamdown (main chat) and MarkdownRenderer (tool
outputs)

Design feedback from Olivia to make tables "breathe" more.

## Test plan
- [ ] Open CoPilot chat and trigger a response containing a table
- [ ] Verify tables no longer have left/right borders
- [ ] Verify increased spacing between rows
- [ ] Check both light and dark modes

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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<h2>Greptile Overview</h2>

<details><summary><h3>Greptile Summary</h3></summary>

Improved CoPilot chat table styling by removing left and right borders
and increasing vertical padding from `py-3` to `py-3.5`. Changes apply
to both:
- Streamdown-rendered tables (via CSS selector in `globals.css`)  
- MarkdownRenderer tables (via Tailwind classes)

The changes make tables "breathe" more per design feedback from Olivia.

**Issue Found:**
- The CSS padding value in `globals.css:192` is `0.625rem` (`py-2.5`)
but should be `0.875rem` (`py-3.5`) to match the PR description and the
MarkdownRenderer implementation.
</details>


<details><summary><h3>Confidence Score: 2/5</h3></summary>

- This PR has a logical error that will cause inconsistent table styling
between Streamdown and MarkdownRenderer tables
- The implementation has an inconsistency where the CSS file uses
`py-2.5` padding while the PR description and MarkdownRenderer use
`py-3.5`. This will result in different table padding between the two
rendering systems, contradicting the goal of consistent styling
improvements.
- Pay close attention to `autogpt_platform/frontend/src/app/globals.css`
- the padding value needs to be corrected to match the intended design
</details>


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<!-- /greptile_comment -->

---------

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
Co-authored-by: coderabbitai[bot] <136622811+coderabbitai[bot]@users.noreply.github.com>

autogpt_platform/frontend/src/app/globals.css

@@ -180,3 +180,14 @@ body[data-google-picker-open="true"] [data-dialog-content] {
   z-index: 1 !important;
   pointer-events: none !important;
 }
+
+/* CoPilot chat table styling — remove left/right borders, increase padding */
+[data-streamdown="table-wrapper"] table {
+  border-left: none;
+  border-right: none;
+}
+
+[data-streamdown="table-wrapper"] th,
+[data-streamdown="table-wrapper"] td {
+  padding: 0.875rem 1rem; /* py-3.5 px-4 */
+}

autogpt_platform/frontend/src/components/contextual/OutputRenderers/renderers/MarkdownRenderer.tsx

@@ -226,7 +226,7 @@ function renderMarkdown(
           table: ({ children, ...props }) => (
             <div className="my-4 overflow-x-auto">
               <table
-                className="min-w-full divide-y divide-gray-200 rounded-lg border border-gray-200 dark:divide-gray-700 dark:border-gray-700"
+                className="min-w-full divide-y divide-gray-200 border-y border-gray-200 dark:divide-gray-700 dark:border-gray-700"
                 {...props}
               >
                 {children}
@@ -235,7 +235,7 @@ function renderMarkdown(
           ),
           th: ({ children, ...props }) => (
             <th
-              className="bg-gray-50 px-4 py-3 text-left text-xs font-semibold uppercase tracking-wider text-gray-700 dark:bg-gray-800 dark:text-gray-300"
+              className="bg-gray-50 px-4 py-3.5 text-left text-xs font-semibold uppercase tracking-wider text-gray-700 dark:bg-gray-800 dark:text-gray-300"
               {...props}
             >
               {children}
@@ -243,7 +243,7 @@ function renderMarkdown(
           ),
           td: ({ children, ...props }) => (
             <td
-              className="border-t border-gray-200 px-4 py-3 text-sm text-gray-600 dark:border-gray-700 dark:text-gray-400"
+              className="border-t border-gray-200 px-4 py-3.5 text-sm text-gray-600 dark:border-gray-700 dark:text-gray-400"
               {...props}
             >
               {children}