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/dotenv/CHANGELOG.md

@@ -0,0 +1,45 @@
+CHANGELOG
+=========
+
+6.2
+---
+
+ * Add a new `filter` argument to `debug:dotenv` command to filter variable names
+
+5.4
+---
+
+ * Add `dotenv:dump` command to compile the contents of the .env files into a PHP-optimized file called `.env.local.php`
+ * Add `debug:dotenv` command to list all dotenv files with variables and values
+ * Add `$overrideExistingVars` on `Dotenv::bootEnv()` and `Dotenv::loadEnv()`
+
+5.1.0
+-----
+
+ * added `Dotenv::bootEnv()` to check for `.env.local.php` before calling `Dotenv::loadEnv()`
+ * added `Dotenv::setProdEnvs()` and `Dotenv::usePutenv()`
+ * made Dotenv's constructor accept `$envKey` and `$debugKey` arguments, to define
+   the name of the env vars that configure the env name and debug settings
+ * deprecated passing `$usePutenv` argument to Dotenv's constructor
+
+5.0.0
+-----
+
+ * using `putenv()` is disabled by default
+
+4.3.0
+-----
+
+ * deprecated use of `putenv()` by default. This feature will be opted-in with a constructor argument to `Dotenv`
+
+4.2.0
+-----
+
+ * added `Dotenv::overload()` and `$overrideExistingVars` as optional parameter of `Dotenv::populate()`
+ * added `Dotenv::loadEnv()` to load a .env file and its corresponding .env.local, .env.$env and .env.$env.local files if they exist
+
+3.3.0
+-----
+
+ * [BC BREAK] Since v3.3.7, the latest Dotenv files override the previous ones. Real env vars are not affected and are not overridden.
+ * added the component