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>

plan-ceo-review/SKILL.md.tmpl

@@ -190,6 +190,8 @@ Feed into the Premise Challenge (0A) and Dream State Mapping (0C). If you find a
 
 {{LEARNINGS_SEARCH}}
 
+{{GBRAIN_CONTEXT_LOAD}}
+
 ## Step 0: Nuclear Scope Challenge + Mode Selection
 
 ### 0A. Premise Challenge
@@ -352,6 +354,7 @@ After mode is selected, confirm which implementation approach (from 0C-bis) appl
 
 Once selected, commit fully. Do not silently drift.
 **STOP.** AskUserQuestion once per issue. Do NOT batch. Recommend + WHY. If no issues or fix is obvious, state what you'll do and move on — don't waste a question. Do NOT proceed until user responds.
+**Reminder: Do NOT make any code changes. Review only.**
 
 ## Review Sections (11 sections, after scope and mode are agreed)
 
@@ -381,6 +384,7 @@ Evaluate and diagram:
 
 Required ASCII diagram: full system architecture showing new components and their relationships to existing ones.
 **STOP.** AskUserQuestion once per issue. Do NOT batch. Recommend + WHY. If no issues or fix is obvious, state what you'll do and move on — don't waste a question. Do NOT proceed until user responds.
+**Reminder: Do NOT make any code changes. Review only.**
 
 ### Section 2: Error & Rescue Map
 This is the section that catches silent failures. It is not optional.
@@ -410,6 +414,7 @@ Rules for this section:
 * For each GAP (unrescued error that should be rescued): specify the rescue action and what the user should see.
 * For LLM/AI service calls specifically: what happens when the response is malformed? When it's empty? When it hallucinates invalid JSON? When the model returns a refusal? Each of these is a distinct failure mode.
 **STOP.** AskUserQuestion once per issue. Do NOT batch. Recommend + WHY. If no issues or fix is obvious, state what you'll do and move on — don't waste a question. Do NOT proceed until user responds.
+**Reminder: Do NOT make any code changes. Review only.**
 
 ### Section 3: Security & Threat Model
 Security is not a sub-bullet of architecture. It gets its own section.
@@ -425,6 +430,7 @@ Evaluate:
 
 For each finding: threat, likelihood (High/Med/Low), impact (High/Med/Low), and whether the plan mitigates it.
 **STOP.** AskUserQuestion once per issue. Do NOT batch. Recommend + WHY. If no issues or fix is obvious, state what you'll do and move on — don't waste a question. Do NOT proceed until user responds.
+**Reminder: Do NOT make any code changes. Review only.**
 
 ### Section 4: Data Flow & Interaction Edge Cases
 This section traces data through the system and interactions through the UI with adversarial thoroughness.
@@ -461,6 +467,7 @@ For each node: what happens on each shadow path? Is it tested?
 ```
 Flag any unhandled edge case as a gap. For each gap, specify the fix.
 **STOP.** AskUserQuestion once per issue. Do NOT batch. Recommend + WHY. If no issues or fix is obvious, state what you'll do and move on — don't waste a question. Do NOT proceed until user responds.
+**Reminder: Do NOT make any code changes. Review only.**
 
 ### Section 5: Code Quality Review
 Evaluate:
@@ -473,6 +480,7 @@ Evaluate:
 * Under-engineering check. Anything fragile, assuming happy path only, or missing obvious defensive checks?
 * Cyclomatic complexity. Flag any new method that branches more than 5 times. Propose a refactor.
 **STOP.** AskUserQuestion once per issue. Do NOT batch. Recommend + WHY. If no issues or fix is obvious, state what you'll do and move on — don't waste a question. Do NOT proceed until user responds.
+**Reminder: Do NOT make any code changes. Review only.**
 
 ### Section 6: Test Review
 Make a complete diagram of every new thing this plan introduces:
@@ -513,6 +521,7 @@ Load/stress test requirements: For any new codepath called frequently or process
 
 For LLM/prompt changes: Check CLAUDE.md for the "Prompt/LLM changes" file patterns. If this plan touches ANY of those patterns, state which eval suites must be run, which cases should be added, and what baselines to compare against.
 **STOP.** AskUserQuestion once per issue. Do NOT batch. Recommend + WHY. If no issues or fix is obvious, state what you'll do and move on — don't waste a question. Do NOT proceed until user responds.
+**Reminder: Do NOT make any code changes. Review only.**
 
 ### Section 7: Performance Review
 Evaluate:
@@ -524,6 +533,7 @@ Evaluate:
 * Slow paths. Top 3 slowest new codepaths and estimated p99 latency.
 * Connection pool pressure. New DB connections, Redis connections, HTTP connections?
 **STOP.** AskUserQuestion once per issue. Do NOT batch. Recommend + WHY. If no issues or fix is obvious, state what you'll do and move on — don't waste a question. Do NOT proceed until user responds.
+**Reminder: Do NOT make any code changes. Review only.**
 
 ### Section 8: Observability & Debuggability Review
 New systems break. This section ensures you can see why.
@@ -540,6 +550,7 @@ Evaluate:
 **EXPANSION and SELECTIVE EXPANSION addition:**
 * What observability would make this feature a joy to operate? (For SELECTIVE EXPANSION, include observability for any accepted cherry-picks.)
 **STOP.** AskUserQuestion once per issue. Do NOT batch. Recommend + WHY. If no issues or fix is obvious, state what you'll do and move on — don't waste a question. Do NOT proceed until user responds.
+**Reminder: Do NOT make any code changes. Review only.**
 
 ### Section 9: Deployment & Rollout Review
 Evaluate:
@@ -555,6 +566,7 @@ Evaluate:
 **EXPANSION and SELECTIVE EXPANSION addition:**
 * What deploy infrastructure would make shipping this feature routine? (For SELECTIVE EXPANSION, assess whether accepted cherry-picks change the deployment risk profile.)
 **STOP.** AskUserQuestion once per issue. Do NOT batch. Recommend + WHY. If no issues or fix is obvious, state what you'll do and move on — don't waste a question. Do NOT proceed until user responds.
+**Reminder: Do NOT make any code changes. Review only.**
 
 ### Section 10: Long-Term Trajectory Review
 Evaluate:
@@ -570,6 +582,7 @@ Evaluate:
 * Platform potential. Does this create capabilities other features can leverage?
 * (SELECTIVE EXPANSION only) Retrospective: Were the right cherry-picks accepted? Did any rejected expansions turn out to be load-bearing for the accepted ones?
 **STOP.** AskUserQuestion once per issue. Do NOT batch. Recommend + WHY. If no issues or fix is obvious, state what you'll do and move on — don't waste a question. Do NOT proceed until user responds.
+**Reminder: Do NOT make any code changes. Review only.**
 
 ### Section 11: Design & UX Review (skip if no UI scope detected)
 The CEO calling in the designer. Not a pixel-level audit — that's /plan-design-review and /design-review. This is ensuring the plan has design intentionality.
@@ -592,6 +605,7 @@ Required ASCII diagram: user flow showing screens/states and transitions.
 
 If this plan has significant UI scope, recommend: "Consider running /plan-design-review for a deep design review of this plan before implementation."
 **STOP.** AskUserQuestion once per issue. Do NOT batch. Recommend + WHY. If no issues or fix is obvious, state what you'll do and move on — don't waste a question. Do NOT proceed until user responds.
+**Reminder: Do NOT make any code changes. Review only.**
 
 {{CODEX_PLAN_REVIEW}}
 
@@ -783,6 +797,8 @@ If promoted, copy the CEO plan content to `docs/designs/{FEATURE}.md` (create th
 
 {{LEARNINGS_LOG}}
 
+{{GBRAIN_SAVE_RESULTS}}
+
 ## Mode Quick Reference
 ```
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