port to Minecraft 26.3

No source changes were needed — nothing JustBackup touches moved in 26.3.
Version bumps only:

- minecraft 26.2 -> 26.3, loader 0.19.3 -> 0.19.5
- fabric-api 0.154.2+26.2 -> 0.160.5+26.3
- fabric.mod.json depends: minecraft ~26.2 -> ~26.3,
  fabricloader >=0.19.3 -> >=0.19.5
- README version line

Verified with `./gradlew build` against 26.3 (clean).

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

README.md

@@ -2,7 +2,7 @@
 
 A fast, space-efficient backup mod for Fabric servers, written by iceBear67.
 
-- **Minecraft 26.2** · Fabric Loader ≥ 0.19.3 · Java 25
+- **Minecraft 26.3** · Fabric Loader ≥ 0.19.5 · Java 25
 - Consistent backups: no torn region files, even while the server is running
 - Incremental backups with **chained restore** (a full base + its incrementals restore as one unit)
 - **Reflink (CoW) fast path**: on btrfs/XFS/ZFS the world is only "frozen" for milliseconds

gradle.properties

@@ -7,8 +7,8 @@ org.gradle.configuration-cache=false
 
 # Fabric Properties
 # check these on https://fabricmc.net/develop
-minecraft_version=26.2
+minecraft_version=26.3
-loader_version=0.19.3
+loader_version=0.19.5
 loom_version=1.17-SNAPSHOT
 
 # Mod Properties
@@ -17,4 +17,4 @@ maven_group=io.ib67.sfcraft
 archives_base_name=justbackup
 
 # Dependencies
-fabric_version=0.154.2+26.2
+fabric_version=0.160.5+26.3

src/main/resources/fabric.mod.json

@@ -19,8 +19,8 @@
 		"justbackup.mixins.json"
 	],
 	"depends": {
-		"fabricloader": ">=0.19.3",
+		"fabricloader": ">=0.19.5",
-		"minecraft": "~26.2",
+		"minecraft": "~26.3",
 		"java": ">=25",
 		"fabric-api": "*"
 	}