docs(runicnpc): stage 9 decisions D306-D314 and its design

The org lead's answers of 2026-10-06: the performance bar is what stages 1
and 5 measured (D306); a separate small-map staging rig (D307) driven by a
daily Gitea CI drill, static and live (D308), with its own panel key in an
org secret (D309); no RunicNPC means every Place NPCs step is refused (D310,
ending D243's fallback); Gitea-only publishing for 1.0 (D311); one player
walk gathering every deferred in-game check (D312); one coordinated cutover
of the five Rust repos (D313); and core's phase label fixed (D314).

Stage 9 is laid out as four phases after this one: 9b hardening, 9c the
staging drill, 9d the player walk, 9e the cutover and release.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01E14m6SuuY6i1vASFeGDBeY

modules/rust/PLAN_REDESIGNS.md

@@ -8,7 +8,7 @@ they can be read together. **Built so far:** §1, walked 2026-09-28 (§1.9); §5
 rig walk still to come (§5.8, D209); §3, built and walked on the rigs and the site 2026-09-29, its in-game
 rows still to come (§3.4); §4, built 2026-09-29 (§4.1). **§6 was spiked on 2026-09-30, and the org lead
 chose neither route: Runic Gateway writes its own NPC plugin, RunicNPC, planned in
-[`../../runicnpc/PLAN.md`](../../runicnpc/PLAN.md) (D214–D242), and the rest of this plan waits for it.**
+[`../../runicnpc/PLAN.md`](../../runicnpc/PLAN.md) (D214–D314), and the rest of this plan waits for it.**
 
 This is a companion to [`PLAN_FIXES.md`](PLAN_FIXES.md) and [`PLAN.md`](PLAN.md). Where they disagree, this
 document is later and wins. Its decisions continue PLAN_FIXES' numbering at **D188**.