feat(vault): track PARA layer (Categories/References/Notes/Daily/Clippings/Tags/Attachments/Presentations)

- Add 8 PARA directories to .gitignore whitelist (234 files)
- Completes dual-layer sync: LLM Wiki layer + PARA personal knowledge layer
- markdown_output/ remains excluded (transit zone)

.gitignore

@@ -4,7 +4,7 @@
 
 /*
 
-# === Tracked content (LLM Wiki layer + infrastructure) ===
+# === Tracked content (LLM Wiki layer + PARA layer + infrastructure) ===
 !raw/
 !wiki/
 !Templates/
@@ -15,12 +15,30 @@
 !.gitattributes
 !.mailmap
 
+# PARA layer (personal knowledge)
+!Categories/
+!References/
+!Notes/
+!Daily/
+!Clippings/
+!Tags/
+!Attachments/
+!Presentations/
+
 # Allow everything inside tracked dirs
 !raw/**
 !wiki/**
 !Templates/**
 !tools/**
 !.githooks/**
+!Categories/**
+!References/**
+!Notes/**
+!Daily/**
+!Clippings/**
+!Tags/**
+!Attachments/**
+!Presentations/**
 
 # === Obsidian config — track but ignore high-churn state/caches ===
 !.obsidian/