fix: keyboard feedback #1644 (#1697)

Addresses reviewer feedback from #1644:
- **Localize keyboard hint strings** — 13 hardcoded English strings
replaced with \`tr()\` macro (\`STR_KB_HINT_*\`), making them
translatable across all 22 languages (fallback to English when not yet
translated)
- **Deduplicate \`Lyra3CoversMetrics\`** — now derives from
\`LyraMetrics\` via lambda copy, overriding only \`homeCoverTileHeight\`
and \`homeRecentBooksCount\` (eliminates ~30 duplicated metric fields)
- **Unify keyboard drawing in \`BaseTheme\`** — \`drawTextField\` and
\`drawKeyboardKey\` overrides removed from \`LyraTheme\`; variability
controlled via \`keyboardKeyCornerRadius\` metric (0=Base, 6=Lyra).
Unified text field padding to 6, adopted Lyra's secondary label draw
order (main first, then secondary)
- **Add URL-optimized keyboard layout** — \`urlLayout\` with \`:\` and
\`/\` replacing \`=\` and \`,\` for easier URL input without switching
to SYM mode
---

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

src/components/themes/lyra/LyraTheme.h

@@ -40,7 +40,8 @@ constexpr ThemeMetrics values = {.batteryWidth = 16,
                                  .keyboardCenteredText = false,
                                  .keyboardVerticalOffset = -7,
                                  .keyboardTextFieldWidthPercent = 85,
-                                 .keyboardWidthPercent = 90};
+                                 .keyboardWidthPercent = 90,
+                                 .keyboardKeyCornerRadius = 6};
 }
 
 class LyraTheme : public BaseTheme {
@@ -71,10 +72,5 @@ class LyraTheme : public BaseTheme {
   void drawEmptyRecents(const GfxRenderer& renderer, const Rect rect) const;
   Rect drawPopup(const GfxRenderer& renderer, const char* message) const override;
   void fillPopupProgress(const GfxRenderer& renderer, const Rect& layout, const int progress) const override;
-  void drawTextField(const GfxRenderer& renderer, Rect rect, const int textWidth, bool cursorMode = false,
-                     int contentStartX = 0, int contentWidth = 0) const override;
-  void drawKeyboardKey(const GfxRenderer& renderer, Rect rect, const char* label, const bool isSelected,
-                       const char* secondaryLabel = nullptr, KeyboardKeyType keyType = KeyboardKeyType::Normal,
-                       bool inactiveSelection = false) const override;
   bool showsFileIcons() const override { return true; }
 };