test(e2e): add venv + playwright deps and robust Matomo API auth flow

- Add optional dependency group "e2e" with Playwright in pyproject.toml
- Teach Makefile to create/use local .venv, install e2e deps, and fetch Chromium
- Wait for Matomo HTTP response (any status) before running bootstrap
- Switch API calls to /index.php and add HttpClient.get()
- Use UsersManager.getTokenAuth (md5Password) to obtain token_auth for privileged calls
- Make web installer more resilient to HTTPError/500 and locale/button variations
- Update E2E test to pass admin email and call API via /index.php

https://chatgpt.com/share/694a70b0-e520-800f-a3e4-eaf5e96530bd

pyproject.toml

@@ -5,7 +5,7 @@ build-backend = "setuptools.build_meta"
 [project]
 name = "matomo-bootstrap"
 version = "0.1.0"
-description = ""
+description = "Headless bootstrap tooling for Matomo (installation + API token provisioning)"
 readme = "README.md"
 requires-python = ">=3.10"
 authors = [{ name = "Kevin Veen-Birkenbach", email = "kevin@veen.world" }]
@@ -14,8 +14,13 @@ urls = { Homepage = "https://github.com/kevinveenbirkenbach/matomo-bootstrap" }
 
 dependencies = []
 
+[project.optional-dependencies]
+e2e = [
+  "playwright>=1.40.0",
+]
+
 [tool.setuptools]
-package-dir = {"" = "src"}
+package-dir = { "" = "src" }
 
 [tool.setuptools.packages.find]
 where = ["src"]