refactor: full-stack restructure with multi-tenancy, workspace management, and K8s diagnostics

- Add Workspace domain (entity, repository, service, handler, DTO)
- Add multi-tenant K8s client with tenant binding and quota management
- Add K8s diagnostics client (instance diagnostics)
- Add authorization middleware (authz package)
- Restructure frontend to feature-based architecture (features/)
- Add User Management page in configuration
- Add AccessDenied page and route guards
- Refactor shared components (form inputs, layout, UI)
- Update Tailwind config for new design system
- Add comprehensive documentation (docs/, tasks/, plans)
- Improve cluster service with better kubeconfig handling
- Add tests for crypto, config, helm client, tenant binding

test/frontend-playwright-smoke.py

@@ -0,0 +1,96 @@
+#!/usr/bin/env python3
+# Covers frontend smoke flows: login, chart browser rendering, launch modal,
+# registry/cluster configuration pages, instances page, and mobile layout sanity.
+
+import os
+from pathlib import Path
+
+from playwright.sync_api import expect, sync_playwright
+
+
+BASE_URL = os.environ.get("FRONTEND_URL", "http://localhost:18080")
+ADMIN_USER = os.environ.get("ADMIN_USER", "admin")
+ADMIN_PASS = os.environ["ADMIN_PASS"]
+
+
+def login(page):
+    page.goto(BASE_URL, wait_until="networkidle")
+    if page.locator("input[type='password']").count() == 0:
+        return
+    text_inputs = page.locator("input:not([type='password'])")
+    text_inputs.first.fill(ADMIN_USER)
+    page.locator("input[type='password']").first.fill(ADMIN_PASS)
+    page.get_by_role("button").filter(has_text="Login").last.click()
+    page.wait_for_url("**/home", timeout=15000)
+    page.wait_for_load_state("networkidle")
+    expect(page.locator("body")).not_to_contain_text("Login failed")
+
+
+def screenshot(page, name):
+    page.screenshot(path=f"/tmp/{name}.png", full_page=True)
+
+
+def click_nav(page, name, index=0):
+    item = page.get_by_role("button", name=name).nth(index)
+    try:
+        item.click(timeout=5000)
+    except Exception:
+        item.evaluate("element => element.click()")
+    page.wait_for_load_state("networkidle")
+    page.wait_for_timeout(500)
+
+
+def record_console_error(errors, msg):
+    text = msg.text
+    ignored = [
+        "Failed to load resource: the server responded with a status of 404",
+        "[LaunchModal] Failed to load values schema",
+    ]
+    if any(item in text for item in ignored):
+        return
+    errors.append(text)
+
+
+with sync_playwright() as p:
+    browser = p.chromium.launch(headless=True)
+    page = browser.new_page(viewport={"width": 1440, "height": 950})
+    errors = []
+    page.on("pageerror", lambda exc: errors.append(str(exc)))
+    page.on("console", lambda msg: record_console_error(errors, msg) if msg.type == "error" else None)
+
+    login(page)
+
+    click_nav(page, "Launch Instance")
+    expect(page.get_by_text("Chart Browser")).to_be_visible(timeout=15000)
+    screenshot(page, "ocdp-chart-browser-desktop")
+    if page.get_by_role("button", name="Launch").count() > 0:
+        page.get_by_role("button", name="Launch").first.click()
+        if page.get_by_role("button", name="Cancel").count() > 0:
+            expect(page.get_by_role("heading", name="Launch Instance")).to_be_visible(timeout=10000)
+            screenshot(page, "ocdp-launch-modal")
+            page.get_by_role("button", name="Cancel").click()
+
+    click_nav(page, "Registries")
+    expect(page.locator("body")).to_contain_text("Registry")
+    screenshot(page, "ocdp-registry-config")
+
+    click_nav(page, "Clusters")
+    expect(page.locator("body")).to_contain_text("Cluster")
+    screenshot(page, "ocdp-cluster-config")
+
+    click_nav(page, "Instances")
+    expect(page.locator("body")).to_contain_text("Instance")
+    screenshot(page, "ocdp-instances")
+
+    mobile = browser.new_page(viewport={"width": 390, "height": 844}, is_mobile=True)
+    login(mobile)
+    click_nav(mobile, "Launch Instance")
+    expect(mobile.get_by_text("Chart Browser")).to_be_visible(timeout=15000)
+    screenshot(mobile, "ocdp-chart-browser-mobile")
+    overflow = mobile.evaluate("document.documentElement.scrollWidth > document.documentElement.clientWidth + 2")
+    assert not overflow, "mobile page has horizontal overflow"
+
+    browser.close()
+
+    if errors:
+        raise AssertionError("\\n".join(errors[:10]))