docs(installer): drop phase references that are now this build's behaviour

Five comments described the patch tier as work a later phase would do. It is
this phase, so they read as stale the moment the code landed.

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

src/servuo.rs

@@ -23,7 +23,7 @@ pub struct ServUoRoot {
     pub path: PathBuf,
     /// `None` when `Server/AssemblyInfo.cs` is absent or unparseable. Reported as "unknown", which
     /// is treated exactly like any other non-57.4 answer: the base install proceeds, and the patch
-    /// tier (Phase 3) takes its unsupported path.
+    /// tier takes its unsupported path.
     pub version: Option<String>,
 }
 
@@ -312,7 +312,7 @@ mod tests {
     #[test]
     fn an_unreadable_version_is_unknown_and_unsupported() {
         // "Unknown" must not be optimistically treated as 57.4: an unreadable version is not
-        // evidence of a good one, and it gates the patch tier in Phase 3.
+        // evidence of a good one, and it is what gates the patch tier.
         let tmp = TempDir::new("rg-test-noversion").unwrap();
         let root = tmp.path().join("srv");
         fake_root(&root);