fix(cli): wipe workspace contents instead of the mount point itself

Regression from the fresh-clone commit: the sync script was doing
`rm -rf \$REPO_ROOT` where \$REPO_ROOT = `/workspace` inside the
daemon-session container — which is the volume/bind mount point. You
can `rm` the CONTENTS of a mount point, but not the directory itself;
unlinking the mount fails with EACCES ("Permission denied"). Every
spawn hit this, leaving spawn_failed with:

    rm: cannot remove '/workspace': Permission denied

Fix: keep the mount point, nuke its contents. `find -mindepth 1
-maxdepth 1 -exec rm -rf {} +` reaches every direct child including
dotfiles (`.git`, `.gitignore`, etc.) and doesn't touch the mount.
Also runs `mkdir -p` before the wipe so first-time spawns still work
when the directory doesn't exist yet.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: jasonczc

cli/src/cloud/workspace/syncRepositoryInContainer.ts

@@ -103,11 +103,15 @@ function buildRepositorySyncScript(params: {
         'echo "[haqi-sync] repoRoot=$REPO_ROOT workspaceBranch=$WORKSPACE_BRANCH baseBranch=$BASE_BRANCH target=$TARGET_LABEL" >&2',
         // Fresh-clone contract: nuke whatever the previous session left
         // behind so sticky branch state never survives across opens.
-        'if [ -d "$REPO_ROOT" ]; then',
-        '  echo "[haqi-sync] removing existing $REPO_ROOT for fresh clone" >&2',
-        '  rm -rf "$REPO_ROOT"',
-        'fi',
+        // NOTE: `$REPO_ROOT` in daemon-session containers is the volume
+        // mount point (typically `/workspace`) — you can't `rm` the
+        // directory itself, only its contents. `find -mindepth 1`
+        // deletes everything inside while leaving the mount intact.
         'mkdir -p "$REPO_ROOT"',
+        'if [ -n "$(ls -A "$REPO_ROOT" 2>/dev/null)" ]; then',
+        '  echo "[haqi-sync] wiping contents of $REPO_ROOT for fresh clone" >&2',
+        '  find "$REPO_ROOT" -mindepth 1 -maxdepth 1 -exec rm -rf {} +',
+        'fi',
         `git clone ${params.repository.cloneDepth ? `--depth ${params.repository.cloneDepth} ` : ''}"$AUTH_REMOTE_URL" "$REPO_ROOT"`
     ]