Swap out primary UI color for Zoo brand blue, add theme color setting to control its hue (#2017)

* Add a setting for themeColor

* Add primary-color to Tailwind, driven by themeColor setting

* Get rid of most uses of "energy" colors

* Change out the rest of the energy colors

* Tweak NetworkHealthIndicator light mode checkmarks

* Handful of other CSS tweaks while I'm here:
- remove the AppHeader bg and border
- pane margins
- better dark mode button styles

* Make Zoo logomark a badge

* A snapshot a day keeps the bugs away! 📷🐛 (OS: ubuntu)

* Re-run CI post-snapshots

* A snapshot a day keeps the bugs away! 📷🐛 (OS: ubuntu)

* Retrigger CI

---------

Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>

src/components/SettingsAuthProvider.tsx

@@ -199,6 +199,17 @@ export const SettingsAuthProviderBase = ({
     return () => matcher.removeEventListener('change', listener)
   }, [settingsState.context])
 
+  /**
+   * Update the --primary-hue CSS variable
+   * to match the setting app.themeColor.current
+   */
+  useEffect(() => {
+    document.documentElement.style.setProperty(
+      `--primary-hue`,
+      settingsState.context.app.themeColor.current
+    )
+  }, [settingsState.context.app.themeColor.current])
+
   // Auth machine setup
   const [authState, authSend, authActor] = useMachine(authMachine, {
     actions: {