test(snapshot): compare snapshot diagnostics without MCP session facts

MCP errors now also carry open-session facts (selection and target at
failure), so the CLI/MCP comparison checks that MCP keeps the CLI's
snapshot details rather than requiring identical objects.

Refs #7442

Co-Authored-By: gensokyo-dev <342580529+gensokyo-dev@users.noreply.github.com>

tests/acceptance/analysisSnapshotDiagnostics.test.ts

@@ -64,7 +64,8 @@ cliTest(
             "Analysis snapshot validation failed at target: Invalid input: expected object, received undefined (2 more issues)",
           );
       }
-      expect(mcpError.details).toEqual(cliError.details);
+      // MCP adds open-session facts; the snapshot reason must match exactly.
+      expect(mcpError.details).toMatchObject(cliError.details);
       expect(await readFile(snapshot, "utf8")).toBe(encoded);
     }
     expect(