fix: preserve file path in config parse errors and fix test assertion

The error standardization lost the file path from parse error messages
when anyhow::Context was removed. Add path field to ParseSettings
variant so errors like "Failed to parse settings file at /path: ..."
include the file location. Also fix test that expected capitalized
"Workflow not found" to match the new lowercase error message.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

lib/crates/fabro-cli/tests/it/cmd/config.rs

@@ -436,10 +436,10 @@ fn settings_local_workflow_name_applies_run_overlay_and_deep_merges() {
 
     // checkpoint.exclude_globs is a security/policy list: replace by default.
     let checkpoint = run_checkpoint(&cfg);
-    assert_eq!(checkpoint.exclude_globs, vec![
-        "run-only".to_string(),
-        "shared".to_string()
-    ]);
+    assert_eq!(
+        checkpoint.exclude_globs,
+        vec!["run-only".to_string(), "shared".to_string()]
+    );
 
     // Hooks: id-based replacement. The "shared" hook appears in both cli and
     // workflow layers and resolves to the workflow entry; project and run-only
@@ -529,9 +529,10 @@ fn settings_local_explicit_workflow_path_uses_workflow_project_layers() {
     assert!(auto_approve_enabled(&cfg));
     // v2 R30: run.prepare.steps replaces the whole ordered list across layers.
     // The highest-precedence layer (workflow) wins.
-    assert_eq!(run_prepare_commands(&cfg), vec![
-        "workflow-setup".to_string()
-    ]);
+    assert_eq!(
+        run_prepare_commands(&cfg),
+        vec!["workflow-setup".to_string()]
+    );
     assert_eq!(run_sandbox(&cfg).preserve, Some(true));
 }
 
@@ -644,7 +645,7 @@ fn settings_missing_run_config_errors() {
     assert!(String::from_utf8_lossy(&output.stdout).trim().is_empty());
     let stderr = String::from_utf8_lossy(&output.stderr);
     assert!(
-        stderr.contains("error: Workflow not found:"),
+        stderr.contains("workflow not found:"),
         "stderr should report missing workflow path, got:\n{stderr}"
     );
     assert!(

lib/crates/fabro-config/src/error.rs

@@ -1,5 +1,7 @@
 use std::path::{Path, PathBuf};
 
+use toml::de::Error as TomlError;
+
 use crate::parse::ParseError;
 use crate::resolve::ResolveError;
 
@@ -11,6 +13,13 @@ fn format_resolve_errors(errors: &[ResolveError]) -> String {
         .join("\n")
 }
 
+fn format_path_suffix(path: Option<&PathBuf>) -> String {
+    match path {
+        Some(p) => format!(" at {}", p.display()),
+        None => String::new(),
+    }
+}
+
 #[derive(Debug, thiserror::Error)]
 pub enum Error {
     #[error("reading config file {path}: {source}")]
@@ -20,9 +29,10 @@ pub enum Error {
         source: std::io::Error,
     },
 
-    #[error("{context}: {source}")]
+    #[error("{context}{}: {source}", format_path_suffix(.path.as_ref()))]
     ParseSettings {
         context: &'static str,
+        path: Option<PathBuf>,
         #[source]
         source: ParseError,
     },
@@ -31,7 +41,7 @@ pub enum Error {
     TomlParse {
         path: PathBuf,
         #[source]
-        source: toml::de::Error,
+        source: TomlError,
     },
 
     #[error("{context}:\n{}", format_resolve_errors(.errors))]
@@ -67,10 +77,22 @@ impl Error {
     }
 
     pub fn parse(context: &'static str, source: ParseError) -> Self {
-        Self::ParseSettings { context, source }
+        Self::ParseSettings {
+            context,
+            path: None,
+            source,
+        }
     }
 
-    pub fn toml_parse(path: &Path, source: toml::de::Error) -> Self {
+    pub fn parse_file(context: &'static str, path: &Path, source: ParseError) -> Self {
+        Self::ParseSettings {
+            context,
+            path: Some(path.to_path_buf()),
+            source,
+        }
+    }
+
+    pub fn toml_parse(path: &Path, source: TomlError) -> Self {
         Self::TomlParse {
             path: path.to_path_buf(),
             source,

lib/crates/fabro-config/src/load.rs

@@ -10,7 +10,7 @@ use crate::{Error, Result, project, user};
 pub fn load_settings_path(path: &Path) -> Result<SettingsLayer> {
     let content = std::fs::read_to_string(path).map_err(|source| Error::read_file(path, source))?;
     let mut layer = parse_settings_layer(&content)
-        .map_err(|err| Error::parse("Failed to parse settings file", err))?;
+        .map_err(|err| Error::parse_file("Failed to parse settings file", path, err))?;
     let base_dir = path.parent().unwrap_or_else(|| Path::new("."));
     resolve_goal_file_paths(&mut layer, base_dir);
     Ok(layer)