style: align action buttons vertically with page title (#1795)

## Summary

* **What is the goal of this PR?** Fix the vertical misalignment between
the "File Manager" title and the action buttons (Upload / New Folder /
Delete Selected).
* **What changes are included?**
- `h2`: `margin-top: 0` → `margin: 0` — removes the default browser
`margin-bottom` that was inflating the height of the header-left flex
container, pushing the calculated flex center below the visual midpoint
of the title text
- `.page-header-left`: `align-items: baseline` → `align-items: center` —
ensures the title and breadcrumbs are center-aligned with each other and
with the buttons

### Before
<img width="1198" height="560" alt="Screenshot From 2026-04-30 22-29-28"
src="https://github.com/user-attachments/assets/b9a43069-cd93-4028-ab21-75be253ed1f0"
/>

### After
<img width="1198" height="560" alt="Screenshot From 2026-04-30 22-48-49"
src="https://github.com/user-attachments/assets/b9977c65-e479-4490-8ec3-15ae99cfccd7"
/>


## Additional Context

Small CSS-only change, no JavaScript or HTML structure touched.

---

### AI Usage

Did you use AI tools to help write this code? _**YES**_

Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>

src/network/html/FilesPage.html

@@ -44,7 +44,7 @@
     }
     h2 {
       color: var(--title-color);
-      margin-top: 0;
+      margin: 0;
     }
     .card {
       background: var(--card-bg);
@@ -63,7 +63,7 @@
     }
     .page-header-left {
       display: flex;
-      align-items: baseline;
+      align-items: center;
       gap: 12px;
       flex-wrap: wrap;
     }