refactor: safe PHP 7.4 modernization

[somethingwithproof]

This PR adds strict typing, short array syntax, and null coalescing operators across the plugin. Standalone infrastructure files were removed per architectural mandate.

[Copilot]

Pull request overview

This PR modernizes the servcheck plugin’s PHP code for PHP 7.4 by enabling strict typing and refactoring legacy array() usage to short array syntax, and it adds a unit test covering static array definitions / notify account label building.

Changes:

• Add declare(strict_types=1); across plugin entrypoints and includes.
• Replace many array(...) constructs with [...] (and related small syntax modernizations).
• Add a unit test validating key lookup arrays and notify account label-building behavior.

Reviewed changes

Copilot reviewed 20 out of 20 changed files in this pull request and generated 6 comments.

Show a summary per file

File	Description
tests/Unit/ArraysDefinitionTest.php	Adds unit coverage for static arrays and notify account label building logic.
setup.php	Adds strict types and modernizes prepared statement argument arrays.
servcheck_test.php	Adds strict types and modernizes multiple prepared statement argument arrays and filter config arrays.
servcheck_proxies.php	Adds strict types and modernizes local arrays / prepared statement argument arrays.
servcheck_process.php	Adds strict types and modernizes prepared statement argument arrays / local arrays.
servcheck_curl_code.php	Adds strict types.
servcheck_ca.php	Adds strict types and modernizes local arrays / prepared statement argument arrays.
poller_servcheck.php	Adds strict types and modernizes prepared statement argument arrays.
locales/po/index.php	Adds strict types.
locales/LC_MESSAGES/index.php	Adds strict types.
locales/index.php	Adds strict types.
index.php	Adds strict types.
includes/tests.php	Adds strict types and refactors arrays; currently introduces fatal syntax errors in cURL option application.
includes/mxlookup.php	Adds strict types and modernizes array initializations.
includes/index.php	Adds strict types.
includes/functions.php	Adds strict types; currently introduces a fatal syntax error in membership check logic.
includes/constants.php	Adds strict types.
includes/arrays.php	Adds strict types and modernizes key static arrays / notify accounts initialization and some field definitions.
.omc/sessions/07529e04-df5c-47a5-9f2b-aa71b09610a4.json	Adds a tool/session artifact file that likely shouldn’t be committed.
.omc/sessions/01068f21-52fc-4525-83a9-8d76d48b18d4.json	Adds a tool/session artifact file that likely shouldn’t be committed.

[somethingwithproof]

Copilot's 6 comments were against d09799b; the corrupted curl_setopt_array/in_array calls and the stray .omc/sessions/*.json files were already fixed by 5a75b27/cfc2fcf and .omc/ is gitignored on this branch now, so I resolved the threads. No Actions runs exist for this branch yet, likely blocked on the first-time-contributor workflow-approval gate. I don't have push access on Cacti/plugin_servcheck to approve it myself; a maintainer will need to approve the run from the Actions tab.