fix(rank): report a tracker that is not UTF-8 instead of a traceback (#639)

* fix(rank): report a tracker that is not UTF-8 instead of a traceback

A job_search_tracker.csv saved with a spreadsheet's plain "CSV" type is
written in the ANSI code page, so one accented company name raised a
UnicodeDecodeError traceback in `rank_state.py candidates` and stopped
/rank at Step 1. Exit 1 with a one-line message instead.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* changelog: place the #639 entry under [Unreleased]

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
Co-authored-by: Mads Lorentzen <madslorentzen_17@hotmail.com>

tools/rank_state.py

@@ -149,11 +149,16 @@ def tracker_pairs(path: Path) -> set[tuple[str, str]]:
     import csv
 
     pairs = set()
-    with path.open(encoding="utf-8-sig", newline="") as fh:
-        for row in csv.DictReader(fh):
-            company, role = norm(row.get("company")), norm(row.get("role"))
-            if company:
-                pairs.add((company, role))
+    try:
+        with path.open(encoding="utf-8-sig", newline="") as fh:
+            for row in csv.DictReader(fh):
+                company, role = norm(row.get("company")), norm(row.get("role"))
+                if company:
+                    pairs.add((company, role))
+    except UnicodeDecodeError:
+        # A spreadsheet's plain "CSV" save writes the ANSI code page (cp1252 on
+        # most Western installs), so any accented company name stops decoding.
+        sys.exit(f"{path} is not UTF-8 text - re-save it as CSV UTF-8")
     return pairs