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/helpers/_icon-link.scss

@@ -0,0 +1,25 @@
+.icon-link {
+  display: inline-flex;
+  gap: $icon-link-gap;
+  align-items: center;
+  text-decoration-color: rgba(var(--#{$prefix}link-color-rgb), var(--#{$prefix}link-opacity, .5));
+  text-underline-offset: $icon-link-underline-offset;
+  backface-visibility: hidden;
+
+  > .bi {
+    flex-shrink: 0;
+    width: $icon-link-icon-size;
+    height: $icon-link-icon-size;
+    fill: currentcolor;
+    @include transition($icon-link-icon-transition);
+  }
+}
+
+.icon-link-hover {
+  &:hover,
+  &:focus-visible {
+    > .bi {
+      transform: var(--#{$prefix}icon-link-transform, $icon-link-icon-transform);
+    }
+  }
+}