Merge branch 'feature/init-name-resolution'

The previous fix used split('.').next() to get the meta stem from the
snapshot path, which only takes the first dot-segment. This broke names
containing dots (e.g. "Name.new" → "Name.new.luau" would produce
"Name.meta.json" instead of "Name.new.meta.json").

Strip the full middleware extension (e.g. ".server.luau", ".txt") from
the snapshot path filename instead. This correctly handles all cases:
  Name.new.luau      → Name.new  → Name.new.meta.json
  _Init.server.luau  → _Init     → _Init.meta.json
  Name.new.txt       → Name.new  → Name.new.meta.json

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/snapshot_middleware/csv.rs

@@ -109,11 +109,15 @@ pub fn syncback_csv<'sync>(
 
         if !meta.is_empty() {
             let parent = snapshot.path.parent_err()?;
-            let meta_stem = snapshot.path
-                .file_name()
-                .and_then(|n| n.to_str())
-                .map(|s| s.split('.').next().unwrap_or(s))
-                .unwrap_or_else(|| new_inst.name.as_str());
+            let meta_stem = snapshot.middleware
+                .and_then(|mw| {
+                    let ext = format!(".{}", crate::syncback::extension_for_middleware(mw));
+                    snapshot.path.file_name()
+                        .and_then(|n| n.to_str())
+                        .and_then(|s| s.strip_suffix(ext.as_str()))
+                        .map(str::to_owned)
+                })
+                .unwrap_or_else(|| new_inst.name.clone());
             fs_snapshot.add_file(
                 parent.join(format!("{meta_stem}.meta.json")),
                 serde_json::to_vec_pretty(&meta).context("cannot serialize metadata")?,

src/snapshot_middleware/lua.rs

@@ -158,11 +158,15 @@ pub fn syncback_lua<'sync>(
 
         if !meta.is_empty() {
             let parent_location = snapshot.path.parent_err()?;
-            let meta_stem = snapshot.path
-                .file_name()
-                .and_then(|n| n.to_str())
-                .map(|s| s.split('.').next().unwrap_or(s))
-                .unwrap_or_else(|| snapshot.new_inst().name.as_str());
+            let meta_stem = snapshot.middleware
+                .and_then(|mw| {
+                    let ext = format!(".{}", crate::syncback::extension_for_middleware(mw));
+                    snapshot.path.file_name()
+                        .and_then(|n| n.to_str())
+                        .and_then(|s| s.strip_suffix(ext.as_str()))
+                        .map(str::to_owned)
+                })
+                .unwrap_or_else(|| snapshot.new_inst().name.clone());
             fs_snapshot.add_file(
                 parent_location.join(format!("{meta_stem}.meta.json")),
                 serde_json::to_vec_pretty(&meta).context("cannot serialize metadata")?,

src/snapshot_middleware/txt.rs

@@ -58,11 +58,15 @@ pub fn syncback_txt<'sync>(
 
         if !meta.is_empty() {
             let parent = snapshot.path.parent_err()?;
-            let meta_stem = snapshot.path
-                .file_name()
-                .and_then(|n| n.to_str())
-                .map(|s| s.split('.').next().unwrap_or(s))
-                .unwrap_or_else(|| new_inst.name.as_str());
+            let meta_stem = snapshot.middleware
+                .and_then(|mw| {
+                    let ext = format!(".{}", crate::syncback::extension_for_middleware(mw));
+                    snapshot.path.file_name()
+                        .and_then(|n| n.to_str())
+                        .and_then(|s| s.strip_suffix(ext.as_str()))
+                        .map(str::to_owned)
+                })
+                .unwrap_or_else(|| new_inst.name.clone());
             fs_snapshot.add_file(
                 parent.join(format!("{meta_stem}.meta.json")),
                 serde_json::to_vec_pretty(&meta).context("could not serialize metadata")?,