Swap published columns for 24 entries from random.md

Retract the seven published columns into drafts/ and promote the 24 per-date
entries split out of Notes/random.md. Bodies are verbatim; titles, subjects
and slugs are new.

Make publication a matter of location. Notes/Notes.11tydata.js gives anything
under Notes/ permalink: false unless tagged `column`; drafts/drafts.11tydata.js
renders drafts at their real permalink under `yarn dev` and excludes them from
collections entirely in a build, so no template can surface one. Publishing is
now `git mv drafts/<file> columns/`, and moving it back retracts it.

Untagged notes were previously rendered into _site/ and deployed — including
Notes/random.md, which was live at /Notes/random/.

columns/2026-05-18-survivors-bias.md

@@ -0,0 +1,17 @@
+---
+title: Survivor's Bias
+date: 2026-05-18
+layout: column.njk
+tags: [column, philosophy]
+permalink: /columns/2026/survivors-bias/
+---
+
+What is consciousness? The thing that leaves the body when your head's cut off.
+
+Don't think - just do. That's the future.
+
+I hate to think that I'm already too old to make something of myself.
+
+The winners write history - Survivor's bias
+
+This reads like productivity porn: inevitably falling from one pile of money into another