New branch based on all the latest additions to develop (previously #423 with massive merge conflicts)

SimpleSAMLphp security warnings were displayed to users using the OneLogin/internal connector, even though these warnings are only relevant to SimpleSAMLphp users.

This PR adds stricter connection type checks to SimpleSAMLphp version warnings to prevent them from displaying to users who are not actually using SimpleSAMLphp authentication.

Behat tests are expected to fail until #447 is merged into develop, all tests on #447 are passing now.

SimpleSAMLphp version and connection type validation

• SimpleSAMLphp is NOT bundled with the plugin (users must download/install separately)
• Only OneLogin is bundled with the plugin.
• We need to check BOTH library detection AND version status AND connection_type together (lines 758, 781, ~820) to ensure warnings ONLY show when SimpleSAMLphp is genuinely configured and in use.

Scenario 1: User is using OneLogin/internal connector with explicit config

• SimpleSAMLphp may or may not be installed on server.
• connection_type = 'internal' (explicitly set in filter) .
• SimpleSAMLphp version not checked because connection_type !== 'simplesamlphp'
• Result: Don't show SimpleSAMLphp warnings.

Scenario 2: User is trying to use SimpleSAMLphp

• SimpleSAMLphp is not installed (library not detected)
• connection_type = 'simplesamlphp' (explicitly set or default)
• Result: Show SimpleSAMLphp error message.

Scenario 3: User is actively using SimpleSAMLphp

• SimpleSAMLphp is installed (library detected)
• connection_type = 'simplesamlphp' (explicitly set or default)
• Result: Show appropriate SimpleSAMLphp version warnings (critical/warning/unknown)

Scenario 4: Ambiguous - we don't know if library is detected, but config says SimpleSAMLphp

• connection_type = 'simplesamlphp' (could be explicitly set OR default value)
• $simplesamlphp_version_status = 'unknown' (can't get library version number)
• Something is up, but we CAN'T KNOW WHAT EXACTLY: a) User wants SimpleSAMLphp but installation is broken/incomplete b) User is using OneLogin but hasn't explicitly set connection_type='internal' (legacy default)
• Result: Check && $connection_type === 'simplesamlphp' and show warning "unable to determine version"

TO DO:
Help users distinguish between cases a) and b) with better messaging.