fix(ci): resolve clippy::indexing_slicing + doctest compile errors

crates/forge_e2e/src/lib.rs

@@ -25,7 +25,7 @@
 //! ```rust,no_run
 //! use forge_e2e::{Scenario, MockLlm, ExpectedTool, ExpectedText};
 //!
-//! # async fn example() -> anyhow::Result<()> {
+//! // Build a scenario declaratively.
 //! let scenario = Scenario::new("agent reads a file then writes a fix")
 //!     .user_says("please fix the typo in README.md")
 //!     .expect_tool_call(ExpectedTool::new("read").arg("path", "README.md"))
@@ -40,9 +40,10 @@
 //!     .user_says("thanks")
 //!     .mock_responds(MockLlm::text_only(ExpectedText::contains("you're welcome")));
 //!
-//! scenario.run().await?;
-//! # Ok(())
-//! # }
+//! // The scenario is a script: the agent runtime reads it step by step.
+//! let (steps, mock_llm) = scenario.into_mock_llm();
+//! assert_eq!(steps.len(), 4); // 2 user_says + 2 expect_tool_call
+//! assert_eq!(mock_llm.remaining(), 3); // 3 mock responses queued
 //! ```
 //!
 //! ## Mock LLM Format

crates/helios-bot/src/cli.rs

@@ -34,12 +34,12 @@ pub enum Command {
 
 pub fn parse_args() -> Result<Command> {
     let args: Vec<String> = std::env::args().skip(1).collect();
-    if args.is_empty() {
-        anyhow::bail!("usage: helios-bot <serve|run> ...");
-    }
-    match args[0].as_str() {
+    let first = args
+        .first()
+        .ok_or_else(|| anyhow::anyhow!("usage: helios-bot <serve|run> ..."))?;
+    match first.as_str() {
         "serve" => {
-            let s = parse_serve(&args[1..])?;
+            let s = parse_serve(args.get(1..).unwrap_or(&[]))?;
             Ok(Command::Serve {
                 bind: s.bind,
                 private_key: s.private_key,
@@ -49,7 +49,7 @@ pub fn parse_args() -> Result<Command> {
             })
         }
         "run" => {
-            let r = parse_run(&args[1..])?;
+            let r = parse_run(args.get(1..).unwrap_or(&[]))?;
             Ok(Command::Run {
                 repo: r.repo,
                 request: r.request,
@@ -77,7 +77,8 @@ fn parse_serve(args: &[String]) -> Result<ServeArgs> {
 
     let mut i = 0;
     while i < args.len() {
-        match args[i].as_str() {
+        let arg = args.get(i).map(String::as_str).unwrap_or("");
+        match arg {
             "--bind" => {
                 bind = args
                     .get(i + 1)
@@ -114,7 +115,7 @@ fn parse_serve(args: &[String]) -> Result<ServeArgs> {
                     .ok_or_else(|| anyhow::anyhow!("--webhook-secret requires a value"))?;
                 i += 2;
             }
-            _ => anyhow::bail!("unknown flag: {}", args[i]),
+            other => anyhow::bail!("unknown flag: {other}"),
         }
     }
 
@@ -140,7 +141,8 @@ fn parse_run(args: &[String]) -> Result<RunArgs> {
 
     let mut i = 0;
     while i < args.len() {
-        match args[i].as_str() {
+        let arg = args.get(i).map(String::as_str).unwrap_or("");
+        match arg {
             "--repo" => {
                 repo = Some(
                     args.get(i + 1)
@@ -165,7 +167,7 @@ fn parse_run(args: &[String]) -> Result<RunArgs> {
                 checkout_dir = Some(PathBuf::from(v));
                 i += 2;
             }
-            _ => anyhow::bail!("unknown flag: {}", args[i]),
+            other => anyhow::bail!("unknown flag: {other}"),
         }
     }
 

crates/helios-bot/src/webhook.rs

@@ -52,7 +52,9 @@ pub fn parse_helios_mention(text: &str, is_issue: bool, in_comment: bool) -> Opt
     // Look for `@helios` (case-insensitive), followed by optional whitespace, then capture the rest.
     let lower = text.to_ascii_lowercase();
     let idx = lower.find("@helios")?;
-    let after = &text[idx + "@helios".len()..];
+    let needle_len = "@helios".len();
+    let after_start = idx.checked_add(needle_len)?;
+    let after = text.get(after_start..)?;
     // Strip leading whitespace and a single optional ':' or ','.
     let trimmed = after
         .trim_start()