test(runner): make example suite checkout-location independent

Diagnostics embed the absolute source path, but normalize() only scrubbed
hex addresses, so expected snapshots baked in the canonical checkout path
(/Users/agra/projects/sx/...). The suite only passed when run from that exact
directory; from a git worktree all 44 path-printing diagnostics mismatched.

Collapse any absolute `.../examples/` or `.../issues/` prefix to the repo-
relative form. The rule runs through normalize(), which is applied identically
to both expected and actual output, so it can only reconcile path noise — it
cannot desync an otherwise-matching pair. No snapshots regenerated.

Suite now reports 350 passed / 0 failed from a worktree as well as the
canonical tree.

tests/run_examples.sh

@@ -31,8 +31,16 @@ if [[ "${1:-}" == "--update" ]]; then
     UPDATE=1
 fi
 
+# Normalize stdout/stderr for snapshot diffing. Applied identically to both
+# expected and actual, so it can only reconcile location/host noise — never
+# desync an otherwise-matching pair. The path rule collapses any absolute
+# `.../examples/` or `.../issues/` prefix (diagnostics embed the source path)
+# down to the repo-relative form, so snapshots are checkout-location independent
+# (canonical tree vs. a git worktree).
 normalize() {
-    sed 's/0x[0-9a-f]\{4,\}/0xADDR/g'
+    sed -E \
+        -e 's/0x[0-9a-f]{4,}/0xADDR/g' \
+        -e 's#(/[^[:space:]]*)?/(examples|issues)/#\2/#g'
 }
 
 # Normalize `sx ir` output for snapshot diffing (host-specific noise + LLVM