v1.5.0: Complete documentation rewrite - 50+ files with AlisaReactionBot style

- Box-style header comments (Project, Author, License) on every file
- Section headers using double-line box decorators
- Feature markers (// ---- FEATURE: XYZ ----) before every major function
- JSDoc comments for EVERY function with @param, @returns, @example
- Inline notes (NOTE, WARNING, TIP) for non-obvious logic
- Footer END markers on every module
- Matched code style to AlisaReactionBot repository
- All files now searchable by feature name via grep

Author: Shinei Nouzen <157171073+Shineii86@users.noreply.github.com>

src/controllers/filter.controller.js

@@ -1,6 +1,49 @@
+/*
+ * ======= • ======= • ======= • ======= • =======• =======
+ * AniKatoAPI — filter.controller.js
+ * Repository: https://github.com/Shineii86/AniKatoAPI
+ *
+ * @description
+ *   Controller for advanced anime filtering. Accepts multiple query
+ *   parameters to filter anime by genre, year, season, type, status,
+ *   and more. All parameters are forwarded to the extractor.
+ *
+ * @exports
+ *   getFilter - Express route handler for GET /api/filter
+ *
+ * @author  Shinei Nouzen
+ * @license MIT
+ * ======= • ======= • ======= • ======= • =======• =======
+ */
+
 import { extractFilter } from "../extractors/filter.extractor.js";
 import { getCache, setCache } from "../helper/cache.helper.js";
 
+// ══════════════════════════════════════════════════════════════
+// CONTROLLER: FILTER
+// ══════════════════════════════════════════════════════════════
+
+// ---- FEATURE: Advanced filter endpoint ----
+/**
+ * Handles GET /api/filter requests. Returns filtered anime list
+ * based on provided query parameters.
+ *
+ * @param {object} req - Express request object
+ * @param {string} req.query.genre - Genre filter (optional)
+ * @param {string} req.query.year - Year filter (optional)
+ * @param {string} req.query.season - Season filter (optional)
+ * @param {string} req.query.type - Type filter (optional)
+ * @param {string} req.query.status - Status filter (optional)
+ * @param {number} req.query.page - Page number (optional, default: 1)
+ * @param {object} res - Express response object
+ * @param {Function} next - Express next middleware function
+ * @returns {void} Sends JSON response with filtered anime list
+ *
+ * @example
+ *   GET /api/filter?genre=action&year=2024&type=tv
+ *   Response: { success: true, results: { anime, pagination, ... } }
+ * NOTE: The cache key uses JSON.stringify of all params for unique caching
+ */
 const getFilter = async (req, res, next) => {
   try {
     const params = req.query;
@@ -9,7 +52,6 @@ const getFilter = async (req, res, next) => {
     if (cached) {
       return res.json({ success: true, results: cached });
     }
-
     const data = await extractFilter(params);
     setCache(cacheKey, data);
     res.json({ success: true, results: data });
@@ -18,4 +60,6 @@ const getFilter = async (req, res, next) => {
   }
 };
 
-export { getFilter };
+export { getFilter };
+
+// ══════════════════════════════════════════════════════════════ END: filter.controller.js