feat: GBrain resolver — brain-first lookup and save-to-brain

New scripts/resolvers/gbrain.ts with two resolver functions:
- GBRAIN_CONTEXT_LOAD: search brain for context before skill starts
- GBRAIN_SAVE_RESULTS: save skill output to brain after completion

Placeholders added to 4 thinking skill templates (office-hours,
investigate, plan-ceo-review, retro). Resolves to empty string on
all hosts except gbrain via suppressedResolvers.

GBRAIN suppression added to all 9 non-gbrain host configs.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

scripts/resolvers/gbrain.ts

@@ -0,0 +1,42 @@
+/**
+ * GBrain resolver — brain-first lookup and save-to-brain for thinking skills.
+ *
+ * GBrain is a "mod" for gstack. When installed, coding skills become brain-aware:
+ * they search the brain for context before starting and save results after finishing.
+ *
+ * These resolvers are suppressed on ALL hosts except gbrain (via suppressedResolvers
+ * in each host config). For non-gbrain hosts, {{GBRAIN_CONTEXT_LOAD}} and
+ * {{GBRAIN_SAVE_RESULTS}} resolve to empty string and vanish from the output.
+ */
+import type { TemplateContext } from './types';
+
+export function generateGBrainContextLoad(_ctx: TemplateContext): string {
+  return `## Brain Context Load
+
+Before starting this skill, search your brain for relevant context:
+
+1. Search GBrain: \`gbrain query "<topic from user request>"\`
+2. If results found, read the top 3 pages for context
+3. Use this brain context to inform your analysis
+
+If GBrain is not available or returns no results, proceed without brain context.`;
+}
+
+export function generateGBrainSaveResults(ctx: TemplateContext): string {
+  const skillSaveMap: Record<string, string> = {
+    'office-hours': 'Save the design document as a brain page: `gbrain put_page` with the design doc content, tagged with the project slug and "design-doc".',
+    'investigate': 'Save the root cause analysis as a brain page: `gbrain put_page` with the investigation findings, tagged with affected files and "investigation".',
+    'plan-ceo-review': 'Save the CEO plan as a brain page: `gbrain put_page` with the scope decisions and vision, tagged with the feature slug and "ceo-plan".',
+    'retro': 'Save the retrospective as a brain page: `gbrain put_page` with the retro output, tagged with the date range and "retro".',
+  };
+
+  const saveInstruction = skillSaveMap[ctx.skillName] || 'Save the skill output as a brain page if the results are worth preserving.';
+
+  return `## Save Results to Brain
+
+After completing this skill, persist the results to your brain for future reference:
+
+${saveInstruction}
+
+Add backlinks to related brain pages if they exist. If GBrain is not available, skip this step.`;
+}

scripts/resolvers/index.ts

@@ -18,6 +18,7 @@ import { generateConfidenceCalibration } from './confidence';
 import { generateInvokeSkill } from './composition';
 import { generateReviewArmy } from './review-army';
 import { generateDxFramework } from './dx';
+import { generateGBrainContextLoad, generateGBrainSaveResults } from './gbrain';
 
 export const RESOLVERS: Record<string, ResolverFn> = {
   SLUG_EVAL: generateSlugEval,
@@ -62,4 +63,6 @@ export const RESOLVERS: Record<string, ResolverFn> = {
   REVIEW_ARMY: generateReviewArmy,
   CROSS_REVIEW_DEDUP: generateCrossReviewDedup,
   DX_FRAMEWORK: generateDxFramework,
+  GBRAIN_CONTEXT_LOAD: generateGBrainContextLoad,
+  GBRAIN_SAVE_RESULTS: generateGBrainSaveResults,
 };