chore: convert upgrades/0.28.79.md → upgrades/NEXT.md so publish triggers (#126)

PR #125 (1f908bd) shipped the upgrade notes as the released-format
`upgrades/0.28.79.md` instead of the publish workflow's expected
`upgrades/NEXT.md` template. The Publish-to-npm job correspondingly logged
"No NEXT.md found — nothing to publish" and skipped, leaving the npm
package at 0.28.78 even though the code is on main.

Rename to NEXT.md and reset package.json to 0.28.78 so the publish
workflow can do its bump-and-rename on merge. No behavioural code
changes — only release machinery.

Co-authored-by: T <t@t.com>
Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: 3 people

package.json

@@ -1,6 +1,6 @@
 {
   "name": "instar",
-  "version": "0.28.79",
+  "version": "0.28.78",
   "description": "Persistent autonomy infrastructure for AI agents",
   "type": "module",
   "main": "dist/index.js",

src/data/builtin-manifest.json

@@ -1,8 +1,8 @@
 {
   "$schema": "./builtin-manifest.schema.json",
   "schemaVersion": 1,
-  "generatedAt": "2026-05-05T02:58:22.332Z",
-  "instarVersion": "0.28.79",
+  "generatedAt": "2026-05-05T03:10:42.243Z",
+  "instarVersion": "0.28.78",
   "entryCount": 187,
   "entries": {
     "hook:session-start": {

upgrades/0.28.79.md upgrades/NEXT.mdupgrades/0.28.79.md renamed to upgrades/NEXT.md

@@ -1,4 +1,4 @@
-# Upgrade Guide — v0.28.79
+# Upgrade Guide — vNEXT
 
 <!-- bump: patch -->