feat(rules): always_on rulebook flag + Scribe-first prompt

Adds rulebooks.always_on (migration 0058) and a new list_always_on_rules
MCP tool so a session-start eager pull can fetch standing rules without
needing an active-project notion. Updates _INSTRUCTIONS so Claude calls
the new tool at session start and codifies engineering rules in Scribe
rather than CLAUDE.md / auto-memory.

Seeds FabledSword family rulebook to always_on=true on migrate, matching
its design role as the cross-project standards rulebook.

Frontend: badge in RulebookListPane for always-on rulebooks; toggle in
RulebookDetailPane header bound to a new toggleAlwaysOn store action.

This is S1+S2 of the rules-consolidation plan (Scribe task #508). S3
(project-scoped rules) and S4 (enter_project handshake) follow.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

frontend/src/api/rulebooks.ts

@@ -5,6 +5,7 @@ export interface Rulebook {
   owner_user_id: number;
   title: string;
   description: string;
+  always_on: boolean;
   created_at: string | null;
   updated_at: string | null;
 }
@@ -65,7 +66,7 @@ export async function createRulebook(data: { title: string; description?: string
   return apiPost("/api/rulebooks", data);
 }
 
-export async function updateRulebook(id: number, data: Partial<{ title: string; description: string }>): Promise<Rulebook> {
+export async function updateRulebook(id: number, data: Partial<{ title: string; description: string; always_on: boolean }>): Promise<Rulebook> {
   return apiPatch(`/api/rulebooks/${id}`, data);
 }
 

frontend/src/components/rules/RulebookDetailPane.vue

@@ -1,5 +1,5 @@
 <script setup lang="ts">
-import { ref, onMounted, watch } from "vue";
+import { ref, computed, onMounted, watch } from "vue";
 import { useRulebooksStore } from "@/stores/rulebooks";
 import { apiGet } from "@/api/client";
 import {
@@ -18,6 +18,10 @@ const store = useRulebooksStore();
 const isCreating = ref(false);
 const newTitle = ref("");
 
+const currentRulebook = computed(() =>
+  store.rulebooks.find((rb) => rb.id === props.rulebookId),
+);
+
 interface ProjectLite { id: number; title: string }
 const projects = ref<ProjectLite[]>([]);
 // Map<project_id, Set<rulebook_id>>
@@ -68,7 +72,17 @@ watch(() => props.rulebookId, () => {/* re-render of isSubscribed from existing
 
 <template>
   <section class="pane">
-    <header><h2>Topics</h2></header>
+    <header>
+      <h2>Topics</h2>
+      <label v-if="currentRulebook" class="always-on-toggle" title="When on, rules from this rulebook load at session start regardless of project context">
+        <input
+          type="checkbox"
+          :checked="currentRulebook.always_on"
+          @change="store.toggleAlwaysOn(currentRulebook.id)"
+        />
+        <span>Always on</span>
+      </label>
+    </header>
     <ul>
       <li
         v-for="t in topics"
@@ -109,7 +123,14 @@ watch(() => props.rulebookId, () => {/* re-render of isSubscribed from existing
 
 <style scoped>
 .pane { background: var(--color-surface, #18181b); padding: 1rem; overflow-y: auto; }
+header { display: flex; align-items: center; justify-content: space-between; gap: 1rem; }
 header h2 { font-family: Fraunces, serif; font-style: italic; margin: 0 0 0.5rem 0; }
+.always-on-toggle {
+  display: flex; align-items: center; gap: 0.4rem;
+  font-size: 0.85rem; opacity: 0.85; cursor: pointer;
+  user-select: none;
+}
+.always-on-toggle input { cursor: pointer; }
 ul { list-style: none; padding: 0; margin: 1rem 0; }
 li { padding: 0.5rem; cursor: pointer; border-radius: 6px; }
 li.active { background: var(--color-primary-bg, rgba(99,102,241,0.15)); }

frontend/src/components/rules/RulebookListPane.vue

@@ -31,6 +31,7 @@ async function submitNew() {
         @click="emit('select', rb.id)"
       >
         <span class="title">{{ rb.title }}</span>
+        <span v-if="rb.always_on" class="always-on-badge" title="Loaded at session start">always on</span>
       </li>
     </ul>
     <div class="new-rulebook">
@@ -50,9 +51,19 @@ async function submitNew() {
 .pane { background: var(--color-surface, #18181b); padding: 1rem; overflow-y: auto; }
 header h2 { font-family: Fraunces, serif; font-style: italic; margin: 0 0 0.5rem 0; }
 ul { list-style: none; padding: 0; margin: 1rem 0; }
-li { padding: 0.5rem; cursor: pointer; border-radius: 6px; }
+li { padding: 0.5rem; cursor: pointer; border-radius: 6px; display: flex; align-items: center; gap: 0.5rem; }
 li.active { background: var(--color-primary-bg, rgba(99,102,241,0.15)); }
 li:hover { background: var(--color-hover, rgba(255,255,255,0.05)); }
+.always-on-badge {
+  font-size: 0.7rem;
+  text-transform: uppercase;
+  letter-spacing: 0.05em;
+  padding: 0.1rem 0.4rem;
+  border-radius: 3px;
+  background: var(--color-accent, rgba(91,74,138,0.25));
+  color: var(--color-accent-fg, inherit);
+  margin-left: auto;
+}
 .new-rulebook { margin-top: 1rem; }
 .new-rulebook input {
   width: 100%; margin-bottom: 0.5rem;

frontend/src/stores/rulebooks.ts

@@ -54,13 +54,19 @@ export const useRulebooksStore = defineStore("rulebooks", () => {
     return rb;
   }
 
-  async function updateRulebook(id: number, data: Partial<Pick<Rulebook, "title" | "description">>) {
+  async function updateRulebook(id: number, data: Partial<Pick<Rulebook, "title" | "description" | "always_on">>) {
     const rb = await api.updateRulebook(id, data);
     const idx = rulebooks.value.findIndex((r) => r.id === id);
     if (idx >= 0) rulebooks.value[idx] = rb;
     return rb;
   }
 
+  async function toggleAlwaysOn(id: number) {
+    const current = rulebooks.value.find((r) => r.id === id);
+    if (!current) return;
+    return updateRulebook(id, { always_on: !current.always_on });
+  }
+
   async function deleteRulebook(id: number) {
     await api.deleteRulebook(id);
     rulebooks.value = rulebooks.value.filter((r) => r.id !== id);
@@ -121,7 +127,7 @@ export const useRulebooksStore = defineStore("rulebooks", () => {
   return {
     rulebooks, topicsByRulebook, rulesByTopic, currentRule, loading,
     fetchRulebooks, fetchTopics, fetchRules, fetchRule,
-    createRulebook, updateRulebook, deleteRulebook,
+    createRulebook, updateRulebook, toggleAlwaysOn, deleteRulebook,
     createTopic, updateTopic, deleteTopic,
     createRule, updateRule, deleteRule,
   };