ui: larger, more visible tab labels (v2.01.03)

- Tab font-size 12px → 14px (matches body text)
- Inactive tabs: muted foreground color so they're clearly readable
  but visually distinct from the active tab
- Active tab: bold + blue (#1a73e8), slightly more padding (8px 18px)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

linux/blitztext/__init__.py

@@ -6,4 +6,4 @@ counterpart to the macOS Blitztext menu bar app: it runs natively on the host
 (not in a container) so it can type into any application via xdotool.
 """
 
-__version__ = "2.01.02"
+__version__ = "2.01.03"

linux/blitztext/gtksettings.py

@@ -750,13 +750,15 @@ class SettingsDialog:
     color: @theme_fg_color;
 }
 notebook.bt-nb tab {
-    padding: 7px 16px;
+    padding: 8px 18px;
     border-radius: 4px 4px 0 0;
 }
 notebook.bt-nb tab label {
-    font-size: 12px;
+    font-size: 14px;
+    color: mix(@theme_fg_color, @theme_bg_color, 0.35);
 }
 notebook.bt-nb tab:checked label {
+    font-size: 14px;
     font-weight: bold;
     color: #1a73e8;
 }