fix(rust): expand grouped use declarations into import bindings

Give each binding of a use tree the import edge that v8 produces for
its equivalent plain use declaration. Preserve aliases, path comments,
separator whitespace, nested prefixes and self/glob binding behavior.

Keep the old group edge as call evidence until the call pass finishes;
exclude per-binding edges from that pass, then remove private markers.
Plain imports and all call edges retain their current-v8 behavior.
AST cache schema 6 -> 7 rejects results written before expansion.

Replace the earlier broad resolver in #4135 with this syntax-only fix.
The resolver is preserved on local branch wip/rust-use-resolver.

On current v8, all 30 new tests and the full 6642-test suite pass.
Fresh ripgrep builds have 864 import edges instead of 247, with every
call unchanged. Existing name-based import rewiring can still produce
wrong matches, just as it does for equivalent plain declarations.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Co-Authored-By: Codex <noreply@openai.com>
(cherry picked from commit 2669ee4f11)

graphify/cache.py

@@ -37,7 +37,7 @@ except Exception:
     _EXTRACTOR_VERSION = "unknown"
 
 # Bump when AST cache-key semantics change independently of the package version.
-_AST_CACHE_SCHEMA = 7  # Python opaque-base/super(args) raw-call markers and nested-class enclosing ids.
+_AST_CACHE_SCHEMA = 8  # Rust `use` groups: one imports_from edge per binding; prior (7): Python opaque-base/super(args) raw-call markers and nested-class enclosing ids.
 
 
 # Per-process memo: distributions() scans site-packages metadata, which is