Document Seamless .co2 paths and fix process-name false positives.

Record Jorg desk compatdata locations for satellite setup; devices list terra; tighten watchers so syncgames argv is not mistaken for Eden.

Co-authored-by: Cursor <[email protected]>

docs/add-game.md

@@ -20,6 +20,18 @@ Effects:
 
 Multiple `--paths` allowed. Globs are expanded at session time.
 
+### Seamless Coop (Souls / Elden Ring)
+
+Modded saves use **`.co2`**, not vanilla `.sl2`. Non-Steam / me3 launchers create a **new** Proton `compatdata/<id>` — not the vanilla Steam AppID folder.
+
+See **[seamless-save-paths.md](seamless-save-paths.md)** for discovery steps and known Jorg desktop paths (reference for satellites — always re-find on each device).
+
+```bash
+find ~/.steam/steam/steamapps/compatdata -name '*.co2'
+```
+
+Point `paths` at the directory that contains the `.co2` (per machine — the compatdata id can differ on `terra` vs `Jorg`). SteamID subfolders usually match across devices on the same Steam account.
+
 ### Platforms
 
 | Value | Meaning |