Add Solr search: EXT:solr 14 integration and JSON search endpoint

Apache Solr 10 runs on a dedicated VPS behind a Caddy HTTPS proxy
(vitecsolr.evomedien.de) because the managed webserver only allows
outgoing standard ports. Credentials stay out of git: the site config
carries %env()% placeholders resolved via putenv() in the git-ignored
config/system/additional.php.

- composer: apache-solr-for-typo3/solr 14.0.0-RC1 (the only line
  compatible with TYPO3 14; final 14.0.0 will arrive via composer update)
- config.yaml: read connection https/443, core_en per language,
  env placeholder credentials; .gitignore covers additional.php
- setup.typoscript: config.index_enable = 1 (page indexing silently
  refuses without it), solr_pi_results JSON renderer registration,
  results highlighting, and content field extraction from tt_content
  rows - the headless JSON output has no TYPO3SEARCH markers, so the
  default page content extraction indexed an empty content field
- SearchJsonRenderer (renderer #27): JSON output for the search plugin
  on /search. GET q/page in; { query, page, resultsPerPage, numFound,
  totalPages, results[], suggestions } out. Disables the page cache per
  request: config.no_cache is gone in TYPO3 v14, and q/page are
  excluded from cHash, so cached variants would collide
- ext_localconf.php: q and page added to cacheHash excludedParameters
- SolrIndexCommand (vitec:solr-index): works the index queue from the
  CLI with connection diagnostics and a --debug single-step mode -
  EXT:solr 14 ships no console commands and the backend button indexes
  one item per click

packages/vitec/ext_localconf.php

@@ -250,3 +250,10 @@ $GLOBALS['TYPO3_CONF_VARS']['SYS']['formEngine']['nodeRegistry'][1750000000] = [
     );
 
 })();
+
+// The JSON search endpoint (SearchJsonRenderer) uses plain `q` and `page` GET
+// parameters. Without this exclusion TYPO3 demands a cHash for them and answers
+// with an error page; the no_cache condition in the Vitecset TypoScript makes
+// sure search responses are rendered fresh instead of sticking in the page cache.
+$GLOBALS['TYPO3_CONF_VARS']['FE']['cacheHash']['excludedParameters'][] = 'q';
+$GLOBALS['TYPO3_CONF_VARS']['FE']['cacheHash']['excludedParameters'][] = 'page';