build: change to strict versions

[Nevoss]

✨ PR Description

Purpose: Update dependency versions to use strict versioning for improved build reliability and deterministic installations.

Main changes:

• Changed LHCI_VERSION from '0.14.x' to specific version '0.14.0' in Lighthouse test action
• Updated commitlint dependencies from version 19 to exact version 19.8.1
• Refactored PR name linter command to use environment variable for PR title

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