chore: move zola infrastructure to deprecated/

Relocate legacy static site generator configuration to clear
namespace for new Rust-based compiler:

- config.toml, netlify.toml
- sass/, templates/ directories
- themes/apollo submodule (updated .gitmodules path)

Content directory preserved at root for compatibility.

deprecated/sass/colors.scss

@@ -0,0 +1,40 @@
+$bg-0: #212A37;
+
+$bg-1: lighten($bg-0, 5%);
+$bg-2: lighten($bg-1, 10%);
+
+:root.dark {
+  --meta-color: #92A3A0;
+
+  --bg-0: #{$bg-0};
+  --bg-1: #{$bg-1};
+  --bg-2: #{$bg-2};
+
+  --text-0: #EFEBEA;
+
+  --primary-color: #BD7A52;
+}
+
+.meta {
+  color: var(--meta-color);
+}
+time {
+  color: var(--meta-color);
+}
+
+$bg-0-light: #F5F4F2;
+
+$bg-1-light: darken($bg-0-light, 2%);
+$bg-2-light: darken($bg-1-light, 8%);
+
+:root.light {
+  --meta-color: #5A6160;
+
+  --bg-0: #{$bg-0-light};
+  --bg-1: #{$bg-1-light};
+  --bg-2: #{$bg-2-light};
+
+  --text-0: #2A2624;
+
+  --primary-color: #BD7A52;
+}

deprecated/sass/custom.scss

@@ -0,0 +1,6 @@
+.content {
+  max-width: 1000px;
+  margin: 0 auto;
+  padding: 0 0.618em;
+  word-wrap: break-word;
+}

deprecated/sass/fira.scss

@@ -0,0 +1,12 @@
+:root {
+    --text-font: 'Fira Sans', sans-serif;
+    --code-font: 'Fira Mono', monospace;
+}
+
+h1, h2, h3, h4, h5, h6 {
+    font-family: var(--code-font) !important;
+}
+
+header {
+    font-family: var(--code-font) !important;
+}