feat: apply MOSS-grounded self-evolution improvements to ADAM

Implements 7 improvements grounded in MOSS paper (arXiv 2605.22794):

1. Transcript capture (§3.4): context_ring buffer in adam-observe.mjs
   captures last 8 events around struggle signals as context_window.

2. Evidence batching (§3.1): new adam-batch.mjs pre-clusters windowed
   journal entries into coherent failure batches by (signal_type, cluster_key).

3. Multi-stage analysis (§3.3): SKILL.md dispatches adam agent in two
   stages (diagnose+plan → implement) with inter-stage validation gate.

4. Pre-apply verification (§3.4): 4-check deterministic gate before
   auto-apply (source entries exist, diagnosis grounded, type-evidence
   match, no conflicting recent proposals).

5. Auto-rollback (§3.5): new adam-rollback.mjs reverts regressed proposals
   detected by A/B measurement, creates regression nudges.

6. Harness self-modification (§1 Table 1): new harness_edit proposal type
   targeting adam's own scripts with stricter gates (confidence≥5, never
   auto-apply, test-suite-gated).

7. Keypoint matrix evaluation (§4.2): 5 capability dimensions
   (tool_selection, scope_discipline, error_recovery, first_attempt,
   build_reliability) scored per batch for structured evaluation.

Test suite: 94 → 114 tests (20 new), all passing.

hooks/adam-observe.mjs

@@ -107,10 +107,15 @@ const CLEAN_RECOVERY_WINDOW = 3;
 const SILENT_DRIFT_THRESHOLD = 5;
 const ERROR_AFTER_RECOVERY_WINDOW = 5;
 const RECENT_RECOVERIES_MAX = 3;
-const STRUGGLE_TYPES = new Set(["tool_error_loop", "dead_end", "retry_loop"]);
+const STRUGGLE_TYPES = new Set([
+  "tool_error_loop", "dead_end", "retry_loop", "weak_agent",
+  "edit_churn", "build_loop", "silent_drift", "error_after_recovery",
+]);
 const ACTIVE_SKILLS_LOOKBACK = 10;
 const TASK_TOOL_MIN = 5;
 const TASK_DIVERSITY_MIN = 3;
+const CONTEXT_RING_SIZE = 8;
+const CONTEXT_EXCERPT_LEN = 200;
 const STATE_MAX_BYTES = 1_000_000;
 
 function safeRead(path, fallback) {
@@ -226,6 +231,20 @@ function activeNames(state, kind) {
   return [...seen];
 }
 
+function excerpt(text, len) {
+  if (!text || typeof text !== "string") return null;
+  return text.length > len ? text.slice(0, len) + "…" : text;
+}
+
+function pushContext(state, entry) {
+  state.context_ring.push(entry);
+  if (state.context_ring.length > CONTEXT_RING_SIZE) state.context_ring.shift();
+}
+
+function snapshotContext(state) {
+  return state.context_ring.length ? state.context_ring.slice() : undefined;
+}
+
 function errorFingerprint(toolResponse) {
   if (!toolResponse) return null;
   let text = "";
@@ -290,6 +309,7 @@ function resetSessionLocal(state) {
   state.recentRecoveries = [];
   state.session_post_count = 0;
   state.tool_window = [];
+  state.context_ring = [];
   state.task_tool_kinds = {};
   state.task_tool_count = 0;
   state.task_corrections = 0;
@@ -316,6 +336,7 @@ function ensureStateDefaults(state) {
   if (typeof state.silentDriftEmitted !== "boolean") state.silentDriftEmitted = false;
   if (!Array.isArray(state.recentRecoveries)) state.recentRecoveries = [];
   if (typeof state.session_post_count !== "number") state.session_post_count = 0;
+  if (!Array.isArray(state.context_ring)) state.context_ring = [];
 }
 
 function main() {
@@ -340,6 +361,7 @@ function main() {
 
   if (event === "UserPromptSubmit") {
     const prompt = (input.prompt || "").slice(0, 200);
+    pushContext(state, { event: "user", prompt: excerpt(prompt, CONTEXT_EXCERPT_LEN), ts });
     if (isCorrection(prompt)) {
       const last = state.tool_window[state.tool_window.length - 1] || {};
       appendJournal({
@@ -406,9 +428,27 @@ function main() {
     const argsHash = djb2(JSON.stringify(input.tool_input || {}));
     const file = (input.tool_input && (input.tool_input.file_path || input.tool_input.path)) || null;
 
+    const toolResponse = input.tool_response;
+    const respExcerpt = (() => {
+      if (!toolResponse) return null;
+      const text = typeof toolResponse === "string" ? toolResponse
+        : typeof toolResponse.content === "string" ? toolResponse.content
+        : null;
+      return excerpt(text, CONTEXT_EXCERPT_LEN);
+    })();
+    pushContext(state, {
+      event: "tool", tool, ts,
+      input_excerpt: excerpt(JSON.stringify(input.tool_input || {}), CONTEXT_EXCERPT_LEN),
+      response_excerpt: respExcerpt,
+      is_error: !!(toolResponse && toolResponse.is_error),
+    });
+
     let struggleEmittedThisTurn = null;
     const emit = (entry) => {
-      if (STRUGGLE_TYPES.has(entry.type)) struggleEmittedThisTurn = entry.type;
+      if (STRUGGLE_TYPES.has(entry.type)) {
+        entry.context_window = snapshotContext(state);
+        struggleEmittedThisTurn = entry.type;
+      }
       appendJournal(entry);
     };