fix(launcher): drop patch-Z.MPQ from default files and migrate old configs

- default-launcher.json files: only Wow-patched.exe from release.
- config-store: strip deprecated patch-Z.MPQ from merged files; rewrite
  launcher.json on load if user still had that entry.
- Docs/scripts examples updated; version 1.0.4.

Co-authored-by: Cursor <cursoragent@cursor.com>

tools/fractured-launcher-electron/README.md

@@ -134,7 +134,7 @@ Do **not** embed a shared admin PAT in a shipped `launcher.json`. Prefer read-on
 
 ## Patch versions (same filenames, different bytes)
 
-The launcher does **not** read Git commits. For **turn-key** updates when asset names stay fixed (`patch-Z.MPQ`, `Wow-patched.exe`, …):
+The launcher does **not** read Git commits. For **turn-key** updates when asset names stay fixed (e.g. **`Wow-patched.exe`** — add more **`files`** entries for any extra MPQs you ship):
 
 1. Ship **`patch-manifest.json`** next to those files on **every** release (Gitea/GitHub attachment). It lists a **`version`** label (any string you bump per release, e.g. `v0.9.0-client`) and a **`sha256`** per **`files[].source`** name.
 2. With **`patch_manifest.enabled`**: true (default in **`default-launcher.json`**), **Download updates** first fetches the manifest from the same release channel. If the files already on disk match those checksums, the player sees **“already match build … (nothing to download)”** — no redundant downloads.
@@ -146,7 +146,7 @@ If **`patch-manifest.json`** is missing on a release, the launcher falls back to
 
 ```bash
 cd /path/to/staging
-node tools/fractured-launcher-electron/scripts/generate-patch-manifest.js v0.9.0-client patch-Z.MPQ Wow-patched.exe > patch-manifest.json
+node tools/fractured-launcher-electron/scripts/generate-patch-manifest.js v0.9.0-client Wow-patched.exe > patch-manifest.json
 ```
 
 Attach **`patch-manifest.json`** together with the MPQ/exe to the GitHub release (CI sync copies it to Gitea with everything else).