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

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

tailwind.config.js

@@ -32,6 +32,7 @@ module.exports = {
   theme: {
     extend: {
       colors: {
+        primary: `oklch(var(--_primary) / <alpha-value>)`,
         ...themeColors,
       },
       fontFamily: {