scaffold PKB directories, templates, and Obsidian Bases

Establishes the knowledge-base substrate the Council now sits on top of:
daily/, inbox/ (+ raw/ for AudioPen drops), notes/, projects/,
reading/, reflections/, reviews/, _templates/. Each folder seeded with
a .gitkeep so the structure is committed even when empty.

Six templates under _templates/ define the canonical shape for each
note type (daily, permanent, project, reading, reflection, fleeting).
Frontmatter includes the type: field so the Bases below can filter on
it without collision with the existing council-* vocabulary.

Five new Obsidian Bases at repo root: notes.base, projects.base (with
active / all views), reading.base (to-read / reading / done views),
reflections.base (combined reflections + weekly + monthly reviews),
and inbox.base (fleeting notes awaiting triage).

Expanded .obsidian/app.json userIgnoreFilters to hide _templates and
scripts from the vault index so they don't clutter the graph, search,
or file explorer.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

inbox.base

@@ -0,0 +1,26 @@
+filters:
+  and:
+    - note.type == "fleeting"
+
+properties:
+  note.captured:
+    displayName: Captured
+  note.source:
+    displayName: Source
+  note.slug:
+    displayName: Slug
+  note.duration_sec:
+    displayName: Duration (s)
+
+views:
+  - type: table
+    name: Inbox (awaiting triage)
+    order:
+      - file.name
+      - captured
+      - source
+      - slug
+      - duration_sec
+    sort:
+      - property: captured
+        direction: DESC