docs(macroplan): split each version into its own page

Move each version's scope checklist and status out of the monolithic
macroplan into a dedicated docs/vX.Y-<slug>.md page; macroplan keeps the
source block, the rollup status, and a one-line summary + link per
version. v0.1 reuses its existing product/technical pages.

Also drop the "Optional column ruler at 80" requirement from v0.6.

docs/v0.9-robustness.md

@@ -0,0 +1,14 @@
+# v0.9 — Robustness
+
+> Part of the [Typoena macro plan](macroplan.md). Requirements and targets:
+> [qfd.md](qfd.md). Load-bearing decisions: [adr.md](adr.md).
+
+**Status:** not started.
+
+- [ ] Crash-safe writes (write to `.tmp`, fsync, rename)
+- [ ] Recover from interrupted push (re-attempt on next save)
+- [ ] SD card removal / reinsert handling
+- [ ] Wi-Fi reconnect with backoff
+- [ ] On-device provisioning + settings screen: SSID, PAT rotation, default
+      remote, commit author (replaces the v0.1 dev-only NVS-flashing path —
+      first release usable by someone who is not the firmware author)