feat: add section-aware TOML key lookup for rust-analyzer config

Make TOML key lookups in `mlint install` commands aware of the
`[rust-analyzer]` section boundaries. Introduce a shared TOML section
parsing utility and refactor `find_key_value` and `find_table_header`
into section-scoped equivalents (`find_key_in_section`,
`build_override_insert`).

Also add a build script to copy `.run/rust-analyzer.toml` to the
workspace root if absent, and add the generated copy to `.gitignore`.

1 files changed, 9 insertions, 0 deletions

diff --git a/build.rs b/build.rs
new file mode 100644
index 0000000..94e3e0d
--- /dev/null
+++ b/build.rs
@@ -0,0 +1,9 @@
+use std::{env::current_dir, fs};
+
+fn main() {
+    let path = current_dir().unwrap().join("rust-analyzer.toml");
+    let template_content = include_str!("./.run/rust-analyzer.toml");
+    if !path.exists() {
+        fs::write(path, template_content).unwrap();
+    }
+}