fix: prevent tool-use marker leakage in toolshim output (#8310)

Signed-off-by: Eugenio La Cava <eugeniolcv@gmail.com>
Signed-off-by: Michael Neale <michael.neale@gmail.com>
Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Co-authored-by: Michael Neale <michael.neale@gmail.com>

.gitignore

@@ -64,6 +64,12 @@ do_not_version/
 
 /working_dir
 
+# Local build scripts and generated snapshot artifacts
+/build.bat
+/build.ps1
+/build_check.ps1
+/crates/goose/src/agents/snapshots/*.snap.new
+
 # Error log artifacts from mcp replay tests
 crates/goose/tests/mcp_replays/*errors.txt