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/bootstrap-grid.scss

@@ -0,0 +1,62 @@
+@import "mixins/banner";
+@include bsBanner(Grid);
+
+$include-column-box-sizing: true !default;
+
+@import "functions";
+@import "variables";
+@import "variables-dark";
+@import "maps";
+
+@import "mixins/breakpoints";
+@import "mixins/container";
+@import "mixins/grid";
+@import "mixins/utilities";
+
+@import "vendor/rfs";
+
+@import "containers";
+@import "grid";
+
+@import "utilities";
+// Only use the utilities we need
+// stylelint-disable-next-line scss/dollar-variable-default
+$utilities: map-get-multiple(
+  $utilities,
+  (
+    "display",
+    "order",
+    "flex",
+    "flex-direction",
+    "flex-grow",
+    "flex-shrink",
+    "flex-wrap",
+    "justify-content",
+    "align-items",
+    "align-content",
+    "align-self",
+    "margin",
+    "margin-x",
+    "margin-y",
+    "margin-top",
+    "margin-end",
+    "margin-bottom",
+    "margin-start",
+    "negative-margin",
+    "negative-margin-x",
+    "negative-margin-y",
+    "negative-margin-top",
+    "negative-margin-end",
+    "negative-margin-bottom",
+    "negative-margin-start",
+    "padding",
+    "padding-x",
+    "padding-y",
+    "padding-top",
+    "padding-end",
+    "padding-bottom",
+    "padding-start",
+  )
+);
+
+@import "utilities/api";