feat: shorten output for grammar fetching and building

New look:

```
./target/debug/hx --grammar build
Building 102 grammars ... done
100 grammars already built
02 grammars built now
    ["bash", "rust"]
```

helix-loader/src/grammar.rs

@@ -89,15 +89,106 @@ pub fn fetch_grammars() -> Result<()> {
     let mut grammars = get_grammar_configs()?;
     grammars.retain(|grammar| !matches!(grammar.source, GrammarSource::Local { .. }));
 
-    run_parallel(grammars, fetch_grammar, "fetch")
+    print!("Fetching {} grammars", grammars.len());
+    let results = run_parallel(grammars, fetch_grammar);
+    println!(" ... done");
+
+    let mut errors = Vec::new();
+    let mut git_updated = Vec::new();
+    let mut git_up_to_date = Vec::new();
+    let mut non_git = Vec::new();
+
+    for res in results {
+        match res {
+            Ok(FetchSuccess {
+                grammar_id,
+                action: FetchAction::GitUpdated { revision },
+            }) => git_updated.push(format!("{grammar_id}->{revision}")),
+            Ok(FetchSuccess {
+                grammar_id,
+                action: FetchAction::GitUpToDate,
+            }) => git_up_to_date.push(grammar_id),
+            Ok(FetchSuccess {
+                grammar_id,
+                action: FetchAction::NonGit,
+            }) => non_git.push(grammar_id),
+            Err(e) => errors.push(e),
+        }
+    }
+
+    // People will easily find the grammar they want that way
+    git_updated.sort_unstable();
+    git_up_to_date.sort_unstable();
+    non_git.sort_unstable();
+
+    if !git_up_to_date.is_empty() {
+        println!("{:02} up to date git grammars", git_up_to_date.len());
+    }
+    if !non_git.is_empty() {
+        println!("{:02} non git grammars", non_git.len());
+        println!("    {:?}", non_git);
+    }
+
+    if !git_updated.is_empty() {
+        println!("{:02} updated grammars", git_updated.len());
+        println!("    {:?}", git_updated);
+    }
+    if !errors.is_empty() {
+        let len = errors.len();
+        println!("{len:02} grammars failed to fetch");
+        for (i, error) in errors.into_iter().enumerate() {
+            println!("    Failure {i:02}/{len:02}: {error}")
+        }
+    }
+
+    Ok(())
 }
 
 pub fn build_grammars(target: Option<String>) -> Result<()> {
-    run_parallel(
-        get_grammar_configs()?,
-        move |grammar| build_grammar(grammar, target.as_deref()),
-        "build",
-    )
+    let grammars = get_grammar_configs()?;
+    print!("Building {} grammars", grammars.len());
+    let results = run_parallel(grammars, move |grammar| {
+        build_grammar(grammar, target.as_deref())
+    });
+    println!(" ... done");
+
+    let mut errors = Vec::new();
+    let mut built = Vec::new();
+    let mut already_built = Vec::new();
+
+    for res in results {
+        match res {
+            Ok(BuildSuccess {
+                grammar_id,
+                action: BuildAction::Built,
+            }) => built.push(grammar_id),
+            Ok(BuildSuccess {
+                grammar_id,
+                action: BuildAction::AlreadyBuilt,
+            }) => already_built.push(grammar_id),
+            Err(e) => errors.push(e),
+        }
+    }
+
+    built.sort_unstable();
+    already_built.sort_unstable();
+
+    if !already_built.is_empty() {
+        println!("{:02} grammars already built", already_built.len());
+    }
+    if !built.is_empty() {
+        println!("{:02} grammars built now", built.len());
+        println!("    {:?}", built);
+    }
+    if !errors.is_empty() {
+        let len = errors.len();
+        println!("{len:02} grammars failed to build");
+        for (i, error) in errors.into_iter().enumerate() {
+            println!("    Failure {i:02}/{len:02}: {error}")
+        }
+    }
+
+    Ok(())
 }
 
 // Returns the set of grammar configurations the user requests.
@@ -126,9 +217,10 @@ fn get_grammar_configs() -> Result<Vec<GrammarConfiguration>> {
     Ok(grammars)
 }
 
-fn run_parallel<F>(grammars: Vec<GrammarConfiguration>, job: F, action: &'static str) -> Result<()>
+fn run_parallel<F, Res>(grammars: Vec<GrammarConfiguration>, job: F) -> Vec<Result<Res>>
 where
-    F: Fn(GrammarConfiguration) -> Result<()> + std::marker::Send + 'static + Clone,
+    F: Fn(GrammarConfiguration) -> Result<Res> + Send + 'static + Clone,
+    Res: Send + 'static,
 {
     let pool = threadpool::Builder::new().build();
     let (tx, rx) = channel();
@@ -146,14 +238,21 @@ where
 
     drop(tx);
 
-    // TODO: print all failures instead of the first one found.
-    rx.iter()
-        .find(|result| result.is_err())
-        .map(|err| err.with_context(|| format!("Failed to {} some grammar(s)", action)))
-        .unwrap_or(Ok(()))
+    rx.iter().collect()
 }
 
-fn fetch_grammar(grammar: GrammarConfiguration) -> Result<()> {
+struct FetchSuccess {
+    grammar_id: String,
+    action: FetchAction,
+}
+
+enum FetchAction {
+    GitUpdated { revision: String },
+    GitUpToDate,
+    NonGit,
+}
+
+fn fetch_grammar(grammar: GrammarConfiguration) -> Result<FetchSuccess> {
     if let GrammarSource::Git {
         remote, revision, ..
     } = grammar.source
@@ -189,16 +288,27 @@ fn fetch_grammar(grammar: GrammarConfiguration) -> Result<()> {
             )?;
             git(&grammar_dir, ["checkout", &revision])?;
 
-            println!(
-                "Grammar '{}' checked out at '{}'.",
-                grammar.grammar_id, revision
-            );
+            Ok(FetchSuccess {
+                grammar_id: grammar.grammar_id,
+                action: FetchAction::GitUpdated { revision },
+            })
+            // println!(
+            //     "Grammar '{}' checked out at '{}'.",
+            //     grammar.grammar_id, revision
+            // );
         } else {
-            println!("Grammar '{}' is already up to date.", grammar.grammar_id);
+            Ok(FetchSuccess {
+                grammar_id: grammar.grammar_id,
+                action: FetchAction::GitUpToDate,
+            })
+            // println!("Grammar '{}' is already up to date.", grammar.grammar_id);
         }
+    } else {
+        Ok(FetchSuccess {
+            grammar_id: grammar.grammar_id,
+            action: FetchAction::NonGit,
+        })
     }
-
-    Ok(())
 }
 
 // Sets the remote for a repository to the given URL, creating the remote if
@@ -245,7 +355,17 @@ where
     }
 }
 
-fn build_grammar(grammar: GrammarConfiguration, target: Option<&str>) -> Result<()> {
+struct BuildSuccess {
+    grammar_id: String,
+    action: BuildAction,
+}
+
+enum BuildAction {
+    Built,
+    AlreadyBuilt,
+}
+
+fn build_grammar(grammar: GrammarConfiguration, target: Option<&str>) -> Result<BuildSuccess> {
     let grammar_dir = if let GrammarSource::Local { path } = &grammar.source {
         PathBuf::from(&path)
     } else {
@@ -285,7 +405,7 @@ fn build_tree_sitter_library(
     src_path: &Path,
     grammar: GrammarConfiguration,
     target: Option<&str>,
-) -> Result<()> {
+) -> Result<BuildSuccess> {
     let header_path = src_path;
     let parser_path = src_path.join("parser.c");
     let mut scanner_path = src_path.join("scanner.c");
@@ -308,12 +428,12 @@ fn build_tree_sitter_library(
         .context("Failed to compare source and binary timestamps")?;
 
     if !recompile {
-        println!("Grammar '{}' is already built.", grammar.grammar_id);
-        return Ok(());
+        return Ok(BuildSuccess {
+            grammar_id: grammar.grammar_id,
+            action: BuildAction::AlreadyBuilt,
+        });
     }
 
-    println!("Building grammar '{}'", grammar.grammar_id);
-
     let mut config = cc::Build::new();
     config
         .cpp(true)
@@ -381,7 +501,10 @@ fn build_tree_sitter_library(
         ));
     }
 
-    Ok(())
+    Ok(BuildSuccess {
+        grammar_id: grammar.grammar_id,
+        action: BuildAction::Built,
+    })
 }
 
 fn needs_recompile(