remove: delete posthog module

PostHog replaced by Umami (analytics.gazperi.com). Tracking script
already in docusaurus.config.ts headTags; posthog-js removed from deps.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/posthog/init.ts

@@ -1,69 +0,0 @@
-import posthog from 'posthog-js';
-import ExecutionEnvironment from '@docusaurus/ExecutionEnvironment';
-
-const POSTHOG_KEY = 'phx_PEujL3LwMCfjwpnqyDtewBbgHZ9F4uoyrtCDjfNo43MHouY8';
-const POSTHOG_HOST = 'https://eu.i.posthog.com';
-
-let initialized = false;
-
-function initPostHog(): void {
-  if (initialized || !ExecutionEnvironment.canUseDOM) return;
-  initialized = true;
-
-  posthog.init(POSTHOG_KEY, {
-    api_host: POSTHOG_HOST,
-    capture_pageview: true,
-    capture_pageleave: true,
-    person_profiles: 'identified_only',
-  });
-
-  document.addEventListener('click', (event) => {
-    const target = event.target as HTMLElement | null;
-    const anchor = target?.closest('a') as HTMLAnchorElement | null;
-    if (!anchor) return;
-
-    const href = anchor.getAttribute('href') ?? '';
-    if (!href || href.startsWith('#')) return;
-
-    const isExternal =
-      /^https?:\/\//.test(href) && !href.includes('gazperi.com');
-
-    if (isExternal) {
-      posthog.capture('outbound_link_clicked', {
-        href,
-        text: anchor.textContent?.trim() ?? '',
-        pathname: window.location.pathname,
-      });
-    } else if (
-      href.startsWith('/') ||
-      href.startsWith('./') ||
-      href.startsWith('../')
-    ) {
-      posthog.capture('internal_nav_clicked', {
-        to: href,
-        text: anchor.textContent?.trim() ?? '',
-        pathname: window.location.pathname,
-      });
-    }
-  });
-}
-
-export function onRouteDidUpdate({location, previousLocation}: {
-  location: {pathname: string};
-  previousLocation: {pathname: string} | null;
-}): void {
-  if (!ExecutionEnvironment.canUseDOM) return;
-  initPostHog();
-
-  if (location.pathname.startsWith('/educacao')) {
-    posthog.capture('docs_entry_visited', {
-      slug: location.pathname,
-      title: document.title,
-      referrer_pathname: previousLocation?.pathname ?? null,
-    });
-  }
-}
-
-if (ExecutionEnvironment.canUseDOM) {
-  initPostHog();
-}