Fix benchmarks suite juvix compile variants (#2717)

The `--target` flag was replaced by subcommands in
https://github.com/anoma/juvix/pull/2700

This PR fixes the benchmark suite to use `juvix compile native` and
`juvix compile wasi`.

In addition this PR adds as `compile-only` target to `juvix-bench`

The compile-only target only compiles the executable for each variant of
each suite. It doesn't actually run the benchmarks. This is useful when
checking that the variant build steps are correct before committing.

Example to run with stack:

```
stack bench --ba 'compile-only'
```

bench/Main.hs

@@ -23,6 +23,7 @@ compileRules = do
   phony "clean" $ do
     putInfo ("Deleting " <> toFilePath resultsDir)
     removePathForcibly resultsDir
+  phony "compile-only" (forM_ suites compileOnlyRules)
   forM_ suites suiteRules
 
 suiteRules :: Suite -> Rules ()
@@ -31,12 +32,34 @@ suiteRules s = do
   csvRules s
   plotRules s
 
+compileOnlyRules :: Suite -> Action ()
+compileOnlyRules s = forM_ (s ^. suiteVariants) (variantBuildAction s)
+
 multiRecipe :: [Path Abs File] -> Action () -> Rules ()
 multiRecipe out howto = map toFilePath out &%> const howto
 
 recipe :: Path Abs File -> Action () -> Rules ()
 recipe out howto = toFilePath out %> const howto
 
+variantBuildAction :: Suite -> Variant -> Action ()
+variantBuildAction s v = (v ^. variantBuild) args
+  where
+    args :: BuildArgs
+    args =
+      BuildArgs
+        { _buildSrc = srcFile,
+          _buildOutDir = outDir
+        }
+    lang :: Lang
+    lang = v ^. variantLanguage
+    srcFile :: Path Abs File
+    srcFile =
+      addExtension'
+        (langExtension lang)
+        (suiteSrcDir s <//> langPath lang <//> suiteBaseFile s)
+    outDir :: Path Abs Dir
+    outDir = variantBinDir s v
+
 variantRules :: Suite -> Variant -> Rules ()
 variantRules s v = do
   action $ do

bench/Variants.hs

@@ -147,7 +147,7 @@ juvixExe =
       _variantColor = getVariantColor JuvixExe,
       _variantRun = runExe,
       _variantBuild = \args ->
-        command_ [] "juvix" (juvixCommon ++ commonOptions args ext)
+        command_ [] "juvix" (juvixCommon ++ ["native"] ++ commonOptions args ext)
     }
   where
     ext :: [String]
@@ -165,7 +165,7 @@ juvixWasm =
       _variantColor = getVariantColor JuvixWasm,
       _variantRun = runWasm,
       _variantBuild = \args ->
-        command_ [] "juvix" (juvixCommon ++ ["--target=wasm32-wasi"] ++ commonOptions args ext)
+        command_ [] "juvix" (juvixCommon ++ ["wasi"] ++ commonOptions args ext)
     }
   where
     ext :: [String]