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/img/transform.svg

@@ -0,0 +1,4 @@
+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 30 30">
+    <path d="M 0 15 a 15 15 0 1 1 30 0 a 15 15 0 1 1 -30 0" fill="white"/>
+    <path d="m25,21l0,-2l-14,0l0,-12l2,0l-3,-3l-3,3l2,0l0,2l-4,0l0,2l4,0l0,8c0,1.1 0.9,2 2,2l8,0l0,2l-2,0l3,3l3,-3l-2,0l0,-2l4,0zm-12,-10l6,0l0,6l2,0l0,-6c0,-1.1 -0.9,-2 -2,-2l-6,0l0,2z" fill="black"/>
+</svg>