fix: correct refspec source in ngit sync to strip refs/heads/ prefix

When syncing, the nostr state stores refs with full names like
refs/heads/master and refs/tags/v1.0.0. Git tracking refs strip the
refs/heads/ prefix, so the tracking ref lives at refs/remotes/origin/master
not refs/remotes/origin/refs/heads/master.

The sync code was interpolating the full nostr_ref_name into the source
side of the refspec, producing the invalid double-prefixed path. Strip
refs/heads/ or refs/tags/ before constructing the tracking ref segment,
consistent with how git_remote_nostr/push.rs already handles this.

2 files changed, 13 insertions, 3 deletions

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 3d58e1d..e6a7721 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -11,6 +11,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 - git server push option passthrough, enabling `-o secret-scanning.skip` for grasp servers
 
+### Fixed
+
+- `ngit sync` using wrong refspec source (`refs/remotes/origin/refs/heads/master` instead of `refs/remotes/origin/master`), causing sync to fail with "src refspec does not match any existing object"
+
 ## [2.2.1] - 2026-02-25
 
 ### Fixed
diff --git a/src/bin/ngit/sub_commands/sync.rs b/src/bin/ngit/sub_commands/sync.rs
index b377ab4..99cd2d8 100644
--- a/src/bin/ngit/sub_commands/sync.rs
+++ b/src/bin/ngit/sub_commands/sync.rs
@@ -130,6 +130,12 @@ pub async fn launch(args: &SubCommandArgs) -> Result<()> {
             if missing_refs.contains(nostr_ref_name) {
                 continue;
             }
+            // strip refs/heads/ or refs/tags/ prefix to get the tracking ref segment
+            // e.g. refs/heads/master -> master, refs/tags/v1.0.0 -> v1.0.0
+            let tracking_ref_name = nostr_ref_name
+                .strip_prefix("refs/heads/")
+                .or_else(|| nostr_ref_name.strip_prefix("refs/tags/"))
+                .unwrap_or(nostr_ref_name.as_str());
             if invalid_nostr_state_ref(nostr_ref_name) {
                 // ensure nostr_state only supports refs/heads and refs/tags/
                 // and not refs/heads/prs/*
@@ -155,11 +161,11 @@ pub async fn launch(args: &SubCommandArgs) -> Result<()> {
                     // dont try and sync push symbolic refs
                 } else if !force_required {
                     refspecs.push(format!(
-                        "refs/remotes/{nostr_remote_name}/{nostr_ref_name}:{nostr_ref_name}",
+                        "refs/remotes/{nostr_remote_name}/{tracking_ref_name}:{nostr_ref_name}",
                     ));
                 } else if *is_grasp_server || args.force {
                     refspecs.push(format!(
-                        "+refs/remotes/{nostr_remote_name}/{nostr_ref_name}:{nostr_ref_name}",
+                        "+refs/remotes/{nostr_remote_name}/{tracking_ref_name}:{nostr_ref_name}",
                     ));
                 } else {
                     not_updated.push(nostr_ref_name);
@@ -167,7 +173,7 @@ pub async fn launch(args: &SubCommandArgs) -> Result<()> {
             } else {
                 // add missing refs
                 refspecs.push(format!(
-                    "refs/remotes/{nostr_remote_name}/{nostr_ref_name}:{nostr_ref_name}",
+                    "refs/remotes/{nostr_remote_name}/{tracking_ref_name}:{nostr_ref_name}",
                 ));
             }
         }