feat(market): historical chart intervals, stats overlay, configurable outline, easier resize

Chart:
- The price chart now plots the historical CoinGecko series with a Live/1H/1D/1W/1M
  interval selector (top-left of the chart). Live = in-session buffer; 1H uses the
  intraday 5-min series, 1D/1W/1M the daily series (via pfSparklineSeries). X-axis
  labels are interval-aware ("~5h"/"~3d"/"~2w"/"~4mo"). Market-tab open kicks the
  self-throttled market_chart fetch so history populates promptly.
- 24H volume + market cap moved from their own row onto the chart's top strip
  (right side, next to the refresh button), reclaiming the empty band above the
  chart; the hero header now holds just the price row + separator.
- More bottom padding under the plot so the time labels and the DRGX/USDT pair
  buttons aren't crowded against the card edges.

Portfolio groups:
- Accent-outline opacity is now configurable per group (0-100%, default 25%) via a
  slider in the editor's Appearance column; applied to the card + preview outline.
- Resize grip enlarged (14->20px) and a live "W x H" size readout is drawn while
  resizing, so shrinking a group to the 4x3 minimum is reliable and visible.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/util/i18n.cpp

@@ -1111,6 +1111,9 @@ void I18n::loadBuiltinEnglish()
         strings_["market_24h"] = "24h";
         strings_["market_24h_volume"] = "24H VOLUME";
         strings_["market_6h"] = "6h";
+        strings_["market_iv_live"] = "Live";
+        strings_["market_vol_short"] = "Vol";
+        strings_["market_cap_short"] = "Cap";
         strings_["market_attribution"] = "Price data from CoinGecko";
         strings_["market_btc_price"] = "BTC PRICE";
         strings_["market_no_history"] = "No price history available";
@@ -1124,6 +1127,7 @@ void I18n::loadBuiltinEnglish()
         strings_["portfolio_color"] = "Color";
         strings_["portfolio_no_icon"] = "None";
         strings_["portfolio_custom_color"] = "Custom color\xE2\x80\xA6";
+        strings_["portfolio_outline_opacity"] = "Outline opacity";
         strings_["portfolio_price"] = "Price";
         strings_["portfolio_price_usd"] = "Market \xC2\xB7 USD";
         strings_["portfolio_price_btc"] = "Market \xC2\xB7 BTC";