docs: explicitly mark forge geiger deprecated (#11893)

Author: onbjerg

crates/forge/src/cmd/geiger.rs

@@ -41,7 +41,7 @@ impl GeigerArgs {
         }
 
         sh_warn!(
-            "`forge geiger` is just an alias for `forge lint --only-lint unsafe-cheatcode`\n"
+            "`forge geiger` is deprecated, as it is just an alias for `forge lint --only-lint unsafe-cheatcode`\n"
         )?;
 
         // Convert geiger command to lint command with specific lint filter

crates/forge/src/opts.rs

@@ -140,7 +140,7 @@ pub enum ForgeSubcommand {
     #[command(visible_alias = "tr")]
     Tree(tree::TreeArgs),
 
-    /// Detects usage of unsafe cheat codes in a project and its dependencies.
+    /// DEPRECATED: Detects usage of unsafe cheat codes in a project and its dependencies.
     ///
     /// This is an alias for `forge lint --only-lint unsafe-cheatcode`.
     Geiger(geiger::GeigerArgs),