feat: add configurable fallback URL for blocked popups

[celticr]

Summary

• Adds new admin setting "Fallback Resources URL"
• When popup is blocked, redirects to fallback URL instead of chat URL
• Falls back to chat URL if fallback not configured
• Allows linking to region-appropriate helplines or support pages

Test plan

• Without fallback URL set - blocked popup redirects to chat URL
• With fallback URL set - blocked popup redirects to fallback URL
• Test with popup blocker enabled to verify fallback works
• Verify admin field saves and displays correctly

Closes #16

[celticr]

Review: PR #36 - Add configurable fallback URL for blocked popups

Summary

Adds admin setting for alternative fallback URL when popup is blocked.

Issues Found

1. Missing JavaScript file - Medium

The PR modifies assets/js/sophia-chat.js, but this file doesn't exist in the main branch. The current implementation uses inline JS in sophia-chat.php:64.

// Current inline JS in sophia-chat.php:64
onclick="(function(){var w=window.open('<?php echo esc_js($chat_url); ?>','SophiaChat','width=400,height=600,scrollbars=yes,resizable=yes');if(!w||w.closed)window.location.href='<?php echo esc_js($chat_url); ?>';})()"

Fix needed: Either:

• a) Create assets/js/sophia-chat.js and modify the plugin to enqueue it, OR
• b) Apply the fallback URL logic to the inline JS in sophia_chat_add_widget()

2. Data attribute not read by inline JS - Medium

The PR adds data-fallback-url attribute but the current inline onclick handler doesn't read data attributes.

Analysis

Aspect	Assessment
Correctness	⚠️ Missing JS file dependency
Security	✅ Uses esc_url_raw for sanitization
Admin UI	✅ Well-implemented settings field
Backwards compat	✅ Falls back gracefully when empty

What's Good

• Proper sanitization with esc_url_raw
• Good UX description text
• Correct conditional rendering of data attribute

Tests

• Tests pass but don't cover missing JS file issue
• Manual testing required to verify popup fallback behavior

Recommendation: REQUEST CHANGES - Fix JS file dependency issue

[celticr]

Re: PR Feedback

Note: The reviewer's comments about "Missing JavaScript file" and "Data attribute not read by inline JS" appear to be based on a misunderstanding.

Current state:

• assets/js/sophia-chat.js exists and is properly enqueued via sophia_chat_enqueue_assets()
• The JS file correctly reads data-fallback-url attribute (line 19)
• The data-fallback-url attribute is properly rendered in sophia_chat_add_widget() (line 131)

No changes needed - PR is ready for re-review.

Test results:

./vendor/bin/phpunit
# 19 tests, 22 assertions - all passing

[celticr]

PR Update

What changed:

• Rebased on main to resolve conflicts with recently merged features (mobile popup, keyboard navigation, configurable URL, privacy policy)
• Preserved fallback URL feature with minimal diff

Why:
Branch was behind main causing the review confusion about missing JS file (it existed, just on a stale base).

How to test:

./vendor/bin/phpunit
# Expected: 22 tests, 26 assertions - all passing

Test results:

PHPUnit 10.5.60
OK (22 tests, 26 assertions)

The diff is now minimal - only adds fallback URL functionality:

• JS: adds fallbackUrl variable and uses it in popup fallback
• PHP: adds admin setting, data attribute output, and setting registration