feat(job_scout): decision log + report annotations

Track per-job decisions across runs so we don't re-evaluate roles.

- state/decisions.json (keyed by URL: company/title/decision/note/date), now
  git-tracked while seen_jobs.json stays local
- --decide "<url>" <status> [note] records a decision; --hide-decided gives an
  undecided-only view; report tags each role inline with its decision
- usage docstring updated
- seed 18 decisions (9 shortlist, 7 skip, 1 paused, 1 maybe); flags Google Staff
  FDE GenAI as the paused prior session

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

.gitignore

@@ -23,7 +23,9 @@ __pycache__/
 # job_scout runtime artifacts (keep scout.py + requirements.txt only)
 job_scout/.venv/
 job_scout/reports/
-job_scout/state/
+job_scout/state/*
+# ...but track the decision log (job application history), not the churny seen-state
+!job_scout/state/decisions.json
 
 # One-off job-board data pulls (debug artifacts)
 *_jd.json