Respect --index-url in uv pip list (#8942)

## Summary

As an oversight, these arguments weren't being respected from the CLI or
elsewhere -- we always hit PyPI, ignored `--exclude-newer`, etc. It has
to do with the way that the `PipOptions` are setup -- there's a global
struct that we pass around everywhere and fill in with defaults, so
there's no type safety to guarantee that we provide whatever it is we
need to use in the command. The newer APIs are much better about this.

Closes #8927.

crates/uv-cli/src/options.rs

@@ -5,7 +5,7 @@ use uv_resolver::PrereleaseMode;
 use uv_settings::{Combine, PipOptions, ResolverInstallerOptions, ResolverOptions};
 
 use crate::{
-    BuildOptionsArgs, IndexArgs, InstallerArgs, Maybe, RefreshArgs, ResolverArgs,
+    BuildOptionsArgs, FetchArgs, IndexArgs, InstallerArgs, Maybe, RefreshArgs, ResolverArgs,
     ResolverInstallerArgs,
 };
 
@@ -163,6 +163,24 @@ impl From<ResolverInstallerArgs> for PipOptions {
     }
 }
 
+impl From<FetchArgs> for PipOptions {
+    fn from(args: FetchArgs) -> Self {
+        let FetchArgs {
+            index_args,
+            index_strategy,
+            keyring_provider,
+            exclude_newer,
+        } = args;
+
+        Self {
+            index_strategy,
+            keyring_provider,
+            exclude_newer,
+            ..PipOptions::from(index_args)
+        }
+    }
+}
+
 impl From<IndexArgs> for PipOptions {
     fn from(args: IndexArgs) -> Self {
         let IndexArgs {