Use anyhow more idiomatically (#31052)

https://github.com/zed-industries/zed/issues/30972 brought up another
case where our context is not enough to track the actual source of the
issue: we get a general top-level error without inner error.

The reason for this was `.ok_or_else(|| anyhow!("failed to read HEAD
SHA"))?; ` on the top level.

The PR finally reworks the way we use anyhow to reduce such issues (or
at least make it simpler to bubble them up later in a fix).
On top of that, uses a few more anyhow methods for better readability.

* `.ok_or_else(|| anyhow!("..."))`, `map_err` and other similar error
conversion/option reporting cases are replaced with `context` and
`with_context` calls
* in addition to that, various `anyhow!("failed to do ...")` are
stripped with `.context("Doing ...")` messages instead to remove the
parasitic `failed to` text
* `anyhow::ensure!` is used instead of `if ... { return Err(...); }`
calls
* `anyhow::bail!` is used instead of `return Err(anyhow!(...));`

Release Notes:

- N/A

crates/dap_adapters/src/go.rs

@@ -1,3 +1,4 @@
+use anyhow::Context as _;
 use dap::{StartDebuggingRequestArguments, adapters::DebugTaskDefinition};
 use gpui::{AsyncApp, SharedString};
 use language::LanguageName;
@@ -59,18 +60,14 @@ impl DebugAdapter for GoDebugAdapter {
             .which(OsStr::new("dlv"))
             .await
             .and_then(|p| p.to_str().map(|p| p.to_string()))
-            .ok_or(anyhow!("Dlv not found in path"))?;
+            .context("Dlv not found in path")?;
 
         let tcp_connection = config.tcp_connection.clone().unwrap_or_default();
         let (host, port, timeout) = crate::configure_tcp_connection(tcp_connection).await?;
 
         Ok(DebugAdapterBinary {
             command: delve_path,
-            arguments: vec![
-                "dap".into(),
-                "--listen".into(),
-                format!("{}:{}", host, port),
-            ],
+            arguments: vec!["dap".into(), "--listen".into(), format!("{host}:{port}")],
             cwd: None,
             envs: HashMap::default(),
             connection: Some(adapters::TcpArguments {