Move remaining static inline styles into dashboard.css, bump Now Playing text size

Three inline style="..." attributes were pure styling with no per-request
data behind them (a hero-block spacing tweak, a trailing note's margin, a
gap between two stacked rows) — moved each into dashboard.css as a scoped
structural selector so future adjustments happen in one place instead of
being split between the template and the stylesheet.

Also bumped .stream-title/.stream-user/.stream-icon in the Now Playing
card one step up the existing --fs-* scale (13px->15px, 12px->13px,
15px->18px) rather than introducing a one-off size.

Documented the "styles belong in CSS, not inline" rule in CLAUDE.md,
with the actual exception: per-request computed values (a meter's width,
a threshold colour) and JS-toggled initial visibility still can't live
in a static stylesheet and are fine to stay inline.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

CLAUDE.md

@@ -42,6 +42,17 @@ the user's Unraid home server. Server-side project directory is still named
     `SCRIPT_NAME` subpath. Server-rendered config (timezone, script root)
     reaches JS through `<body data-*>`, never string-interpolated into a
     script block.
+  - **No `style="..."` attributes for anything static.** A one-off tweak
+    (button height, a margin, a font size) belongs in the matching
+    `static/css/*.css` file, scoped with a structural selector (an
+    adjacent-sibling or `:last-child` rule tied to the surrounding markup)
+    or a small modifier class — not inline on the element. The only
+    legitimate inline `style=` left in `dashboard.html` are per-request
+    computed values Jinja has to interpolate (a meter's `width: {{ pct
+    }}%`, a colour chosen by threshold) and JS-toggled initial visibility
+    (`display:none` on something `dashboard.js` reveals) — those can't
+    live in a static stylesheet. Everything else should read as a class
+    name, not a value.
 - **`static/css/base.css`** — the single source of truth for the design
   tokens, shared by all three templates: surfaces, a 6-step `--fs-*` type
   scale, semantic colours, and `--tap: 44px` for minimum touch targets.