refactor: Cleanup git state - commit all staged changes

Major refactoring cleanup:
- Add new controller architecture (class-controller-*.php)
- Add new settings-v2 UI (views/settings-v2/)
- Add new CSS architecture (agentic-sidebar.css, tokens)
- Add esbuild build pipeline (scripts/build.js, package.json)
- Add composer dependencies (vendor/)
- Add frontend src directory (assets/js/src/index.jsx)
- Add documentation files
- Remove old/obsolete files (class-settings.php, old CSS)

This commits all pending changes from previous refactoring efforts.

vendor/symfony/polyfill-mbstring/Resources/unidata/caseFolding.php

@@ -0,0 +1,119 @@
+<?php
+
+return [
+    'İ' => 'i̇',
+    'µ' => 'μ',
+    'ſ' => 's',
+    'ͅ' => 'ι',
+    'ς' => 'σ',
+    'ϐ' => 'β',
+    'ϑ' => 'θ',
+    'ϕ' => 'φ',
+    'ϖ' => 'π',
+    'ϰ' => 'κ',
+    'ϱ' => 'ρ',
+    'ϵ' => 'ε',
+    'ẛ' => 'ṡ',
+    'ι' => 'ι',
+    'ß' => 'ss',
+    'ʼn' => 'ʼn',
+    'ǰ' => 'ǰ',
+    'ΐ' => 'ΐ',
+    'ΰ' => 'ΰ',
+    'և' => 'եւ',
+    'ẖ' => 'ẖ',
+    'ẗ' => 'ẗ',
+    'ẘ' => 'ẘ',
+    'ẙ' => 'ẙ',
+    'ẚ' => 'aʾ',
+    'ẞ' => 'ss',
+    'ὐ' => 'ὐ',
+    'ὒ' => 'ὒ',
+    'ὔ' => 'ὔ',
+    'ὖ' => 'ὖ',
+    'ᾀ' => 'ἀι',
+    'ᾁ' => 'ἁι',
+    'ᾂ' => 'ἂι',
+    'ᾃ' => 'ἃι',
+    'ᾄ' => 'ἄι',
+    'ᾅ' => 'ἅι',
+    'ᾆ' => 'ἆι',
+    'ᾇ' => 'ἇι',
+    'ᾈ' => 'ἀι',
+    'ᾉ' => 'ἁι',
+    'ᾊ' => 'ἂι',
+    'ᾋ' => 'ἃι',
+    'ᾌ' => 'ἄι',
+    'ᾍ' => 'ἅι',
+    'ᾎ' => 'ἆι',
+    'ᾏ' => 'ἇι',
+    'ᾐ' => 'ἠι',
+    'ᾑ' => 'ἡι',
+    'ᾒ' => 'ἢι',
+    'ᾓ' => 'ἣι',
+    'ᾔ' => 'ἤι',
+    'ᾕ' => 'ἥι',
+    'ᾖ' => 'ἦι',
+    'ᾗ' => 'ἧι',
+    'ᾘ' => 'ἠι',
+    'ᾙ' => 'ἡι',
+    'ᾚ' => 'ἢι',
+    'ᾛ' => 'ἣι',
+    'ᾜ' => 'ἤι',
+    'ᾝ' => 'ἥι',
+    'ᾞ' => 'ἦι',
+    'ᾟ' => 'ἧι',
+    'ᾠ' => 'ὠι',
+    'ᾡ' => 'ὡι',
+    'ᾢ' => 'ὢι',
+    'ᾣ' => 'ὣι',
+    'ᾤ' => 'ὤι',
+    'ᾥ' => 'ὥι',
+    'ᾦ' => 'ὦι',
+    'ᾧ' => 'ὧι',
+    'ᾨ' => 'ὠι',
+    'ᾩ' => 'ὡι',
+    'ᾪ' => 'ὢι',
+    'ᾫ' => 'ὣι',
+    'ᾬ' => 'ὤι',
+    'ᾭ' => 'ὥι',
+    'ᾮ' => 'ὦι',
+    'ᾯ' => 'ὧι',
+    'ᾲ' => 'ὰι',
+    'ᾳ' => 'αι',
+    'ᾴ' => 'άι',
+    'ᾶ' => 'ᾶ',
+    'ᾷ' => 'ᾶι',
+    'ᾼ' => 'αι',
+    'ῂ' => 'ὴι',
+    'ῃ' => 'ηι',
+    'ῄ' => 'ήι',
+    'ῆ' => 'ῆ',
+    'ῇ' => 'ῆι',
+    'ῌ' => 'ηι',
+    'ῒ' => 'ῒ',
+    'ῖ' => 'ῖ',
+    'ῗ' => 'ῗ',
+    'ῢ' => 'ῢ',
+    'ῤ' => 'ῤ',
+    'ῦ' => 'ῦ',
+    'ῧ' => 'ῧ',
+    'ῲ' => 'ὼι',
+    'ῳ' => 'ωι',
+    'ῴ' => 'ώι',
+    'ῶ' => 'ῶ',
+    'ῷ' => 'ῶι',
+    'ῼ' => 'ωι',
+    'ff' => 'ff',
+    'fi' => 'fi',
+    'fl' => 'fl',
+    'ffi' => 'ffi',
+    'ffl' => 'ffl',
+    'ſt' => 'st',
+    'st' => 'st',
+    'ﬓ' => 'մն',
+    'ﬔ' => 'մե',
+    'ﬕ' => 'մի',
+    'ﬖ' => 'վն',
+    'ﬗ' => 'մխ',
+];