fix(resolver): expand root branch-alias and self.version replace links

Two related parity gaps surfaced by the `circular-dependency` fixture:

1. The root's `extra.branch-alias` entry was never materialized in the
   pool, and root-level `replace`/`provide`/`conflict` constraints
   written as `self.version` were forwarded verbatim. Mirror Composer's
   `RootAliasPackage`: resolve `self.version` against the root's
   declared version for the base entry, then add an extra alias entry
   (carrying the base links plus a duplicate link per `self.version`
   original retagged at the alias's version) when the root's version
   matches an `extra.branch-alias` key.

2. `Pool::matches_package` returned on the first link to a target name
   even when its constraint did not match the query, hiding any later
   link to the same target. With the alias above, that masked the
   second `replace` link tagged at the alias version. Keep iterating
   when target matches but constraint does not, so a later link can
   still satisfy.

1 files changed, 1 insertions, 0 deletions

diff --git a/crates/mozart-registry/src/lockfile.rs b/crates/mozart-registry/src/lockfile.rs
index 5114fb7..701a6f7 100644
--- a/crates/mozart-registry/src/lockfile.rs
+++ b/crates/mozart-registry/src/lockfile.rs
@@ -1679,6 +1679,7 @@ mod tests {
             locked_package_names: IndexSet::new(),
             locked_packages: Vec::new(),
             block_abandoned: false,
+            root_branch_alias: None,
         };
 
         let resolved = resolve(&resolve_request)