Fixes for M-02 to M-14, G-01 to G-14, K-02 to K-04, X-04 to X-14, not yet reviewed

Committed before review so Windows and WSL builds can start.
Each fix was tested and mutation-checked here; the codex review
of each item is still to come, so tasks/BUGS.md stays unticked.

M-02 is mid-review: round 1 findings are fixed (apps/ely-mark/src/tally.rs).
K-01 stays deferred. The ElyMark window test mark-outside.sh failed
once at its crash-recovery step in the last run; not yet looked into.

apps/ely-tree/src/tools.rs

@@ -97,6 +97,16 @@ fn launch(editor: &Path, file: &Path) -> io::Result<()> {
         .map_err(|error| io::Error::other(format!("{}: {error}", editor.display())))
 }
 
+/// Only macOS opens a terminal; elsewhere it is hidden.
+pub const TERMINAL: bool = cfg!(target_os = "macos");
+
+/// The reveal entry, named for this platform's file browser.
+pub const REVEAL: &str = if cfg!(target_os = "macos") {
+    "tree.tool.reveal"
+} else {
+    "tree.tool.reveal_folder"
+};
+
 #[cfg(target_os = "macos")]
 fn terminal_at(dir: &Path) -> io::Result<()> {
     Command::new("open")