Eliminate Python dependency: embed frontend assets in odoo-go

- Copy all OWL frontend assets (JS/CSS/XML/fonts/images) into frontend/
  directory (2925 files, 43MB) — no more runtime reads from Python Odoo
- Replace OdooAddonsPath config with FrontendDir pointing to local frontend/
- Rewire bundle.go, static.go, templates.go, webclient.go to read from
  frontend/ instead of external Python Odoo addons directory
- Auto-detect frontend/ and build/ dirs relative to binary in main.go
- Delete obsolete Python helper scripts (tools/*.py)

The Go server is now fully self-contained: single binary + frontend/ folder.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

frontend/web/static/lib/bootstrap/scss/mixins/_table-variants.scss

@@ -0,0 +1,24 @@
+// scss-docs-start table-variant
+@mixin table-variant($state, $background) {
+  .table-#{$state} {
+    $color: color-contrast(opaque($body-bg, $background));
+    $hover-bg: mix($color, $background, percentage($table-hover-bg-factor));
+    $striped-bg: mix($color, $background, percentage($table-striped-bg-factor));
+    $active-bg: mix($color, $background, percentage($table-active-bg-factor));
+    $table-border-color: mix($color, $background, percentage($table-border-factor));
+
+    --#{$prefix}table-color: #{$color};
+    --#{$prefix}table-bg: #{$background};
+    --#{$prefix}table-border-color: #{$table-border-color};
+    --#{$prefix}table-striped-bg: #{$striped-bg};
+    --#{$prefix}table-striped-color: #{color-contrast($striped-bg)};
+    --#{$prefix}table-active-bg: #{$active-bg};
+    --#{$prefix}table-active-color: #{color-contrast($active-bg)};
+    --#{$prefix}table-hover-bg: #{$hover-bg};
+    --#{$prefix}table-hover-color: #{color-contrast($hover-bg)};
+
+    color: var(--#{$prefix}table-color);
+    border-color: var(--#{$prefix}table-border-color);
+  }
+}
+// scss-docs-end table-variant