docs: Add box-style headers, section headers, feature markers, JSDoc, inline notes, footers

Added comprehensive documentation following project conventions:

Box-style headers (added/fixed where missing):
- All 17 files now have standard Project/Author/License headers

Section headers (// == == SECTION == ==):
- cache.helper.js: LRU CACHE CLASS, TTL CONFIGURATION, SINGLETON, EXPORTED HELPERS
- download.controller.js: DOWNLOAD LINKS HANDLER
- download.extractor.js: BASE64 DECODER, REDIRECT FOLLOWER, DOWNLOAD LINKS EXTRACTOR
- seasons.extractor.js: SEASONS EXTRACTOR
- watchOrder.extractor.js: WATCH ORDER EXTRACTOR
- extractPages.helper.js: PAGE EXTRACTOR
- pagination.helper.js: PAGINATION METADATA

Feature markers (// --- FEATURE: XYZ ---):
- cache.helper.js: LRU Cache, Per-Endpoint TTL, Cache Get/Set/Clear
- download.controller.js: Download Links
- download.extractor.js: Base64 Download Data Decoder, Redirect Chain Resolver, Download Links Extraction
- seasons.extractor.js: Season Information Extraction
- watchOrder.extractor.js: Watch Order / Related Anime Extraction
- streamResolver.extractor.js: Server Name Normalization, Stream URL Resolution, Batch Stream URL Resolution, M3U8 Quality Parser, Subtitle Track Extractor
- mirror.helper.js: Mirror Domain Configuration, Mirror Health Check, Working Mirror Discovery, Mirror Cache Reset, URL Builder, Resilient Fetch with Mirror Fallback, Mirror Status Reporter
- pagination.helper.js: Pagination Metadata Generator
- creatorInfo.js: Creator Attribution Object, Response Creator Injection Middleware

Function-level JSDoc (added/fixed):
- cache.helper.js: Full JSDoc on all 6 class methods (constructor, get, set, delete, clear, getStats, has) and 4 exported helpers

Inline notes for non-obvious logic:
- cache.helper.js: Lazy expiration, LRU re-insertion, singleton pattern
- download.extractor.js: HTML/JSON hybrid response handling, multiple selectors for different mirrors, redirect fallback
- random.extractor.js: maxRedirects, validateStatus, responseURL extraction
- schedule.extractor.js: Dual selector pattern for different mirror layouts
- animeInfo.extractor.js: Positional .bmeta selector fragility
- homeInfo.extractor.js: Dual selector for different layouts
- mirror.helper.js: 404 vs connection error handling
- animeInfo.controller.js: Accept both id and slug params

Footers (added where missing):
- cache.helper.js, download.controller.js, download.extractor.js, seasons.extractor.js, watchOrder.extractor.js, extractPages.helper.js, mirror.helper.js

All 68 source files now have complete documentation coverage (6/6 checks).

src/extractors/streamResolver.extractor.js

@@ -45,6 +45,7 @@ const EMBED_API_MAP = {
   "embed.bunkrerrer.com": "megaplay-1.buzz",
 };
 
+// ---- FEATURE: Server Name Normalization ----
 /**
  * Normalizes server display names to clean identifiers
  * @param {string} name - Raw server name (e.g., "VidPlay-1")
@@ -55,6 +56,7 @@ const normalizeServerName = (name) => {
   return SERVER_NAME_MAP[name] || name.toLowerCase().replace(/[-\s]+\d+$/, "").trim();
 };
 
+// ---- FEATURE: Stream URL Resolution ----
 /**
  * Resolves the actual video stream URL from an embed player page.
  * Extracts data-id from the embed HTML, then queries the megaplay API.
@@ -166,6 +168,7 @@ const resolveStreamUrl = async (embedUrl, options = {}) => {
   }
 };
 
+// ---- FEATURE: Batch Stream URL Resolution ----
 /**
  * Resolves stream URLs for multiple episodes in batch
  * @param {string} embedUrl - The embed player URL
@@ -185,6 +188,7 @@ const resolveStreamUrls = async (embedUrl, options = {}) => {
 // M3U8 PARSER
 // ══════════════════════════════════════════════════════════════
 
+// ---- FEATURE: M3U8 Quality Parser ----
 /**
  * Parses an M3U8 playlist to extract available quality options.
  * Supports both master playlists (multiple qualities) and media playlists.
@@ -265,6 +269,7 @@ const parseM3u8Qualities = async (m3u8Url, options = {}) => {
 // SUBTITLE EXTRACTOR
 // ══════════════════════════════════════════════════════════════
 
+// ---- FEATURE: Subtitle Track Extractor ----
 /**
  * Extracts subtitle information from API response data
  * @param {object} apiData - The megaplay API response