chore: untrack session scratch files (.bd2_*, .watch_targets.py)

Swept in by git add -A during /save; added to .gitignore.
.watch_targets.py kept on disk (in use by background reconnect watcher).

.bd2_ids.txt

@@ -1,7 +0,0 @@
-f269118d-93cf-48a3-96ae-5a9acaf154c9 BD:DESKTOP-KQSL232
-811e345f-ba2f-45a4-bd6e-4dd1ccf37793 BD:DESKTOP-MD6UQI3
-455d1284-febc-4280-b4df-f44be051120e BD:DESKTOP-TRCIEJA
-3baffe0b-f17a-46b6-a418-60cf3802c11b BD:SALES4-PC
-b0cb408c-a699-4737-a772-525503e2dab1 BD:Laptop4
-a4623704-ec6e-4855-8a37-e463734f4293 INSTALL:DESKTOP-F94M8UT
-d1806aa3-9711-4f54-9a41-fd334efd8fd3 INSTALL:NurseAssist

.gitignore

@@ -133,3 +133,5 @@ temp/
 # Transient coord softfail queue (machine-local; drains on /sync, never committed)
 .claude/coord-queue.jsonl
 .boot.bin
+.bd2_*
+.watch_targets.py

.watch_targets.py

@@ -1,5 +0,0 @@
-import json,sys
-d=json.load(sys.stdin)
-t={'DESKTOP-F94M8UT','NurseAssist','DESKTOP-KQSL232','DESKTOP-MD6UQI3','DESKTOP-TRCIEJA','SALES4-PC','Laptop4'}
-on=[a['hostname'] for a in d if a.get('hostname') in t and a.get('status')=='online']
-print(','.join(sorted(on)))