docs: enhance documentation structure and clarify repository layout

- Updated the README and various documentation files to reflect the new flat layout of the `gregFramework`, emphasizing the direct placement of repositories like `gregMod.<Name>/` and `gregExt.<Name>/` under `gregFramework/`.
- Added details about the `gregModmanager/` and `gregDataCenterExporter/` directories, clarifying their roles and contents.
- Improved descriptions and links throughout the documentation to ensure consistency and accuracy, enhancing user navigation and understanding of the project structure.
- Adjusted language in several sections to better communicate the purpose and organization of the repositories.

This commit improves the overall clarity and usability of the documentation.

docs/guides/contributors/contributor-workshop.md

@@ -115,7 +115,7 @@ After publishing, the app re-downloads the item from Steam and replaces your loc
 
 ## Extending the service layer
 
-The `SteamWorkshopService` in `WorkshopUploader/Services/SteamWorkshopService.cs` wraps the Facepunch.Steamworks 2.3.3 API. Key methods:
+The `SteamWorkshopService` in `gregModmanager/Services/SteamWorkshopService.cs` wraps the Facepunch.Steamworks 2.3.3 API. Key methods:
 
 | Method | Purpose |
 |--------|---------|

docs/guides/players/enduser-workshop.md

@@ -21,7 +21,7 @@ This guide is for players who want to **install and manage mods** for Data Cente
 
 ## Installation
 
-You can run WorkshopManager from **any folder you prefer** (for example `Program Files`, Desktop, Downloads, or `<Data Center install>/WorkshopUploader/`).
+You can run WorkshopManager from **any folder you prefer** (for example `Program Files`, Desktop, Downloads, or a folder next to the game). **Source code** for the app lives in the repo folder **`gregModmanager/`** (release ZIPs ship `WorkshopUploader.exe` / **Gregtools Modmanager**).
 
 ### Option A — Installer setup (recommended)