v0.316.3: the content column sits closer to the top and the sidebar

.app-page carried the mockup's 32px 48px 64px, but the .content wrapper it lives in already
supplies 2rem (1rem on a phone). The two added up: 64px from the top and 80px from the sidebar,
which is the gap the operator called too big. .app-page now adds no top or side padding of its
own — .content's is the page's — and keeps only the extra room at the bottom.

Reported from the rendered page with DevTools open, where both paddings are visible at once. The
mockup's numbers were the TOTAL the page should show, not an amount to add to what was already
there.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_0117kRTSgs3rJWUFGxyoWN6Y

CHANGELOG.md

@@ -1,5 +1,12 @@
 ## v0.316.3 — the app page as one column, finished (2026-10-15)
 
+- **The column sat too far from the top and the sidebar.** `.app-page` carried the mockup's
+  `32px 48px 64px`, but the `.content` wrapper it lives in already supplies `2rem` (1rem on a
+  phone) — so the real gap was 64px from the top and 80px from the sidebar. `.app-page` now adds
+  no top or side padding of its own, only the extra room at the bottom. Reported by the operator
+  from the rendered page with DevTools open; the two paddings are visible there as `.content`
+  `padding: 2rem` and `.app-page` `padding: 32px 48px 64px`.
+
 **MinAgent: 0.155.0** (unchanged). A third number in one evening, and each one is the rule working:
 a version is pushed once, so a fix found after a push gets the next patch number rather than a
 second push of the old one.