docs: update documentation to reflect actual registry behavior

Author: Zendevve

docs/Architecture/Overview.md

@@ -21,14 +21,17 @@ OpenTweak scans for installed games across multiple launchers, fetches tweak rec
 **In scope:**
 - Game discovery from Steam, Epic, GOG, Xbox, Manual
 - PCGamingWiki Cargo API integration
-- Config file modification (INI, CFG, JSON, XML, Registry)
+- Config file modification (INI, CFG, JSON, XML)
 - Automatic backup and restore
 - Windows 11 WPF UI with Mica backdrop
 
 **Out of scope:**
 - Game installation/management
 - Online multiplayer modifications
 - Cheat/hack detection bypass
+- **Registry modifications** (explicitly blocked at validation)
+
+> **Note:** Registry modifications are not supported. The TweakEngine validates recipes and marks any with `TargetType.Registry` as unsupported. The PCGWService skips registry extraction entirely.
 
 ---
 
@@ -66,7 +69,6 @@ flowchart TB
         GOG[GOG Registry]
         Xbox[Xbox Game Pass]
         Files[Config Files]
-        Reg[Windows Registry]
     end
 
     MW --> MVM
@@ -83,7 +85,6 @@ flowchart TB
     PCGW --> PCGW_API
     TE --> BS
     TE --> Files
-    TE --> Reg
     BS --> Files
     DBS --> G
     DBS --> TR
@@ -110,15 +111,13 @@ flowchart LR
         Cargo[Cargo API]
         Wiki[Wiki Parse API]
         Files[File System]
-        Reg[Registry]
     end
 
     UI --Commands--> Services
     UI --INPC--> UI
     PCGW_API --HTTP--> Cargo
     PCGW_API --HTTP--> Wiki
     TE_API --> Files
-    TE_API --> Reg
     BS_API --> Files
 ```
 

docs/Features/PCGWIntegration.md

@@ -41,17 +41,16 @@ flowchart TD
     SaveGames --> Pattern2[Regex: {{Game data/saves|...}}]
 
     Recipes --> IniFixes[ExtractIniFixes]
-    Recipes --> RegFixes[ExtractRegistryFixes]
     Recipes --> CmdFixes[ExtractCommandLineFixes]
 
     IniFixes --> ParseCode[Parse <pre> blocks]
-    RegFixes --> ParseReg[Parse registry patterns]
     CmdFixes --> ParseCmd[Parse launch options]
 
     ParseCode --> CreateRecipes[Create TweakRecipe objects]
-    ParseReg --> CreateRecipes
     ParseCmd --> CreateRecipes
 
+    Note1[NOTE: ExtractRegistryFixes returns empty list - Registry not supported] -.-> Recipes
+
     CreateRecipes --> Cache[Cache to LiteDB]
     Cache --> Display[Display in GameDetailView]
 ```
@@ -155,14 +154,15 @@ OpenTweak/1.0 (Automated Game Tweaks)
 | Type | Pattern | Example |
 |------|---------|---------|
 | INI | `[Section]\nKey=Value` | `[Graphics]\nMotionBlur=0` |
-| Registry | `HKEY_...\Key\Value` | `HKEY_CURRENT_USER\Game\Setting` |
 | Command Line | `-argument` | `-novid -high` |
 
+> **Not Extracted:** Registry patterns are NOT extracted. `ExtractRegistryFixes` returns an empty list because the TweakEngine blocks registry modifications.
+
 ### Extraction Methods
 
 1. **ExtractIniFixes**: Parses `<pre>` blocks and INI-style patterns
-2. **ExtractRegistryFixes**: Matches registry key/value patterns
-3. **ExtractCommandLineFixes**: Finds launch option arguments
+2. **ExtractCommandLineFixes**: Finds launch option arguments
+3. ~~ExtractRegistryFixes~~: Returns empty list (registry not supported)
 
 ---
 

docs/Features/TweakEngine.md

@@ -11,7 +11,9 @@ Tests: [`OpenTweak.Tests/Services/TweakEngineTests.cs`](../../OpenTweak.Tests/Se
 
 ## Summary
 
-Safely applies configuration tweaks with automatic backup and restore capabilities. Supports INI, CFG, JSON, XML files, and Windows Registry modifications. Uses Salaros.ConfigParser to preserve comments in config files.
+Safely applies configuration tweaks with automatic backup and restore capabilities. Supports INI, CFG, JSON, and XML config files. Uses Salaros.ConfigParser to preserve comments in config files.
+
+> **Note:** Registry modifications are NOT supported. The engine explicitly blocks registry tweaks at validation with the reason "Registry modifications are not yet implemented safely." This is a deliberate safety decision.
 
 ---
 
@@ -44,7 +46,6 @@ flowchart TD
     ApplyEach --> Ini[ApplyIniTweakAsync]
     ApplyEach --> Json[ApplyJsonTweakAsync]
     ApplyEach --> Xml[ApplyXmlTweakAsync]
-    ApplyEach --> Reg[ApplyRegistryTweak]
 
     Ini --> UseParser[Use Salaros.ConfigParser]
     UseParser --> PreserveComments[Preserve comments]
@@ -159,7 +160,8 @@ public class Snapshot
 | INI/CFG | `ApplyIniTweakAsync` | Salaros.ConfigParser |
 | JSON | `ApplyJsonTweakAsync` | System.Text.Json |
 | XML | `ApplyXmlTweakAsync` | System.Xml.XmlDocument |
-| Registry | `ApplyRegistryTweak` | Microsoft.Win32.Registry |
+
+> **Not Supported:** Registry modifications are blocked at validation. Recipes with `TargetType.Registry` are marked `IsSupported=false` and filtered from the UI.
 
 ### Environment Variable Expansion