CLI: propagate alias rename errors, doctor config resilience

aliases: rename now propagates every meta.json I/O and parse error
instead of silently ignoring failures. Previously, a corrupt or
unreadable meta.json after directory rename would leave the alias
in an inconsistent state with no user-visible error.

doctor: Config::load failure now falls back to Config::default()
with a warning instead of aborting the entire health check. Doctor
should still run diagnostics even when config is missing or corrupt
— that's exactly when you need it most.

src/cli/aliases.rs

@@ -304,16 +304,22 @@ fn cmd_rename(names: &[String], robot: bool, start: Instant) -> Result<(), Swagg
         ))
     })?;
 
-    // Update meta.json alias field
+    // Update meta.json alias field -- propagate errors so the cache
+    // doesn't end up with a stale alias name in metadata.
     let meta_path = new_dir.join("meta.json");
-    if let Ok(bytes) = std::fs::read(&meta_path)
-        && let Ok(mut meta) = serde_json::from_slice::<CacheMetadata>(&bytes)
-    {
-        meta.alias = new.clone();
-        if let Ok(updated_bytes) = serde_json::to_vec_pretty(&meta) {
-            let _ = std::fs::write(&meta_path, updated_bytes);
-        }
-    }
+    let meta_bytes = std::fs::read(&meta_path).map_err(|e| {
+        SwaggerCliError::Cache(format!("failed to read meta.json after rename: {e}"))
+    })?;
+    let mut meta: CacheMetadata = serde_json::from_slice(&meta_bytes).map_err(|e| {
+        SwaggerCliError::Cache(format!("failed to parse meta.json after rename: {e}"))
+    })?;
+    meta.alias = new.clone();
+    let updated_bytes = serde_json::to_vec_pretty(&meta).map_err(|e| {
+        SwaggerCliError::Cache(format!("failed to serialize meta.json after rename: {e}"))
+    })?;
+    std::fs::write(&meta_path, updated_bytes).map_err(|e| {
+        SwaggerCliError::Cache(format!("failed to write meta.json after rename: {e}"))
+    })?;
 
     // Update config if old was the default
     let cfg_path = config_path(None);

src/cli/cache_cmd.rs

@@ -32,8 +32,8 @@ pub struct Args {
     #[arg(long)]
     pub prune_stale: bool,
 
-    /// Days before an alias is considered stale (default: 90)
-    #[arg(long, default_value_t = 90)]
+    /// Days before an alias is considered stale (default: 30, matching config)
+    #[arg(long, default_value_t = 30)]
     pub prune_threshold: u32,
 
     /// Evict least-recently-used aliases until total size is under this limit (MB)
@@ -290,13 +290,13 @@ fn execute_prune(args: &Args, robot: bool, start: Instant) -> Result<(), Swagger
             "cache",
             start.elapsed(),
         );
-    } else if stale.is_empty() {
+    } else if pruned.is_empty() {
         println!(
             "No stale aliases (threshold: {} days).",
             args.prune_threshold
         );
     } else {
-        println!("Pruned {} stale alias(es).", stale.len());
+        println!("Pruned {} stale alias(es).", pruned.len());
     }
     Ok(())
 }

src/cli/doctor.rs

@@ -344,12 +344,19 @@ fn try_fix_alias(cm: &CacheManager, alias: &str) -> Result<Vec<String>, Vec<Stri
 pub async fn execute(args: &Args, robot_mode: bool) -> Result<(), SwaggerCliError> {
     let start = Instant::now();
 
-    // Load config
+    // Load config -- doctor should work even when config is missing or
+    // corrupt, so fall back to defaults and report a warning.
     let cfg_path = config_path(None);
-    let config = Config::load(&cfg_path)?;
+    let mut warnings: Vec<String> = Vec::new();
+    let config = match Config::load(&cfg_path) {
+        Ok(cfg) => cfg,
+        Err(e) => {
+            warnings.push(format!("could not load config (using defaults): {e}"));
+            Config::default()
+        }
+    };
 
     // Check config dir exists
-    let mut warnings: Vec<String> = Vec::new();
     if let Some(parent) = cfg_path.parent()
         && !parent.exists()
     {