todos: a backburner column, and the parked items on it

backburner joins TODO_STATUSES and the board's columns; the three items in the
backburner theme move onto the status, so parked is now a lane rather than a
folder you have to remember to open.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

todo/backburner/four-foreign-keys-are-over-postgres-s-63.md

@@ -2,7 +2,7 @@
 id: backburner/four-foreign-keys-are-over-postgres-s-63
 title: "Four foreign keys are over Postgres's 63-character limit and re-create on every `db:push`"
 theme: backburner
-status: open
+status: backburner
 created: 2026-08-19
 date_source: stated
 order: 1

todo/backburner/music-tagging-feature.md

@@ -2,7 +2,7 @@
 id: backburner/music-tagging-feature
 title: "Music tagging feature"
 theme: backburner
-status: open
+status: backburner
 created: 2026-08-20
 date_source: assumed
 order: 2

todo/backburner/resurrect-projects-apps.md

@@ -2,7 +2,7 @@
 id: backburner/resurrect-projects-apps
 title: "Resurrect Projects/Apps"
 theme: backburner
-status: open
+status: backburner
 created: 2026-08-25
 date_source: stated
 order: 3