docs(readme): introduce EcoQoS mode [ci skip]

Author: mokurin000

README.md

@@ -2,6 +2,22 @@
 
 EnergyStar alernative in Rust.
 
+## Suggested CPU
+
+> [reference](https://devblogs.microsoft.com/performance-diagnostics/introducing-ecoqos/#supported-hardware)
+
+- Intel: 10gen or newer (not 12gen)
+- AMD: Ryzen 5000 Series or newer
+- Qualcomm: Basically all
+
+## I only want to throttle blacklisted ones
+
+See [fitgirl-ecoqos](https://github.com/RustyStarX/fitgirl-ecoqos),
+a tool that forces FitGirl repack unpacker processes to run on E-cores
+(Efficiency cores) for better system resource management.
+
+You can customize it's blacklist. It's by default a set of decompressors.
+
 ## Roadmap
 
 - [x] Multi Window support
@@ -18,12 +34,32 @@ EnergyStar alernative in Rust.
   > You must run `RustyStar.exe` as administrator to throttle them!
 - [ ] Configurable whitelist and blacklist
 
-## Non-goals (for now)
+## What is the efficiency mode?
 
-- Power mode aware, e.g. pause & recover on AC supply
-- Useless bloated GUI
-- Extremely lightweight binary (never prioritier than project maintainability)
+The "Efficiency mode" in task manager does two things on a process:
+
+- Enable EcoQoS
+- Change base priority to IDLE
 
-## Status
+The latter is not always useful, especially when we throttle mostly all processes.
+And the former requires hardware support to perform the best effect.
 
-Partially functional.
+[`EcoQoS`](https://devblogs.microsoft.com/performance-diagnostics/introducing-ecoqos/) was
+first introduced in Windows 10 Preview Build 21359.
+
+The main impact from EcoQoS are:
+  - Energy efficiency & Sustainability
+  - Reduced heat and fan noise (where this project actually care)
+
+## What does EcoQoS actually do?
+
+According to [MSDN](https://learn.microsoft.com/en-us/windows/win32/procthread/quality-of-service#quality-of-service-levels),
+`Eco` QoS level means:
+
+> Always selects most efficient CPU frequency and schedules
+
+## Non-goals
+
+- Useless bloated GUI
+- Power mode awareness, e.g. pause & recover on AC supply
+- Extremely lightweight binary