fix: resolve publish blockers for v3.7.4→v3.8.0 release

- Fix #1991 crash: optional chaining for task-history sessionID access
- Fix #1992 think-mode: add antigravity entries to HIGH_VARIANT_MAP
- Fix #1949 Copilot premium misattribution: use createInternalAgentTextPart
- Fix #1982 load_skills: pass directory to discoverSkills for project-level skills
- Fix command priority: sort scopePriority before .find(), project-first return
- Fix Google provider transform: apply in userFallbackModels path
- Fix ralph-loop TUI: optional chaining for event handler
- Fix runtime-fallback: unify dual fallback engines, remove HTTP 400 from retry,
  fix pendingFallbackModel stuck state, add priority gate to skip model-fallback
  when runtime-fallback is active
- Fix Prometheus task system: exempt from todowrite/todoread deny
- Fix background_output: default full_session to true
- Remove orphan hooks: hashline-edit-diff-enhancer (redundant with hashline_edit
  built-in diff), task-reminder (dead code)
- Remove orphan config entries: 3 stale hook names from Zod schema
- Fix disabled_hooks schema: accept arbitrary strings for forward compatibility
- Register json-error-recovery hook in tool-guard pipeline
- Add disabled_hooks gating for question-label-truncator, task-resume-info,
  claude-code-hooks
- Update test expectations to match new behavior

src/hooks/runtime-fallback/auto-retry.ts

@@ -9,6 +9,9 @@ import { SessionCategoryRegistry } from "../../shared/session-category-registry"
 
 const SESSION_TTL_MS = 30 * 60 * 1000
 
+declare function setTimeout(callback: () => void | Promise<void>, delay?: number): ReturnType<typeof globalThis.setTimeout>
+declare function clearTimeout(timeout: ReturnType<typeof globalThis.setTimeout>): void
+
 export function createAutoRetryHelpers(deps: HookDeps) {
   const { ctx, config, options, sessionStates, sessionLastAccess, sessionRetryInFlight, sessionAwaitingFallbackResult, sessionFallbackTimeouts, pluginConfig } = deps
 
@@ -87,6 +90,10 @@ export function createAutoRetryHelpers(deps: HookDeps) {
     const modelParts = newModel.split("/")
     if (modelParts.length < 2) {
       log(`[${HOOK_NAME}] Invalid model format (missing provider prefix): ${newModel}`)
+      const state = sessionStates.get(sessionID)
+      if (state?.pendingFallbackModel) {
+        state.pendingFallbackModel = undefined
+      }
       return
     }
 
@@ -96,6 +103,7 @@ export function createAutoRetryHelpers(deps: HookDeps) {
     }
 
     sessionRetryInFlight.add(sessionID)
+    let retryDispatched = false
     try {
       const messagesResp = await ctx.client.session.messages({
         path: { id: sessionID },
@@ -136,6 +144,7 @@ export function createAutoRetryHelpers(deps: HookDeps) {
             },
             query: { directory: ctx.directory },
           })
+          retryDispatched = true
         }
       } else {
         log(`[${HOOK_NAME}] No user message found for auto-retry (${source})`, { sessionID })
@@ -144,6 +153,14 @@ export function createAutoRetryHelpers(deps: HookDeps) {
       log(`[${HOOK_NAME}] Auto-retry failed (${source})`, { sessionID, error: String(retryError) })
     } finally {
       sessionRetryInFlight.delete(sessionID)
+      if (!retryDispatched) {
+        sessionAwaitingFallbackResult.delete(sessionID)
+        clearSessionFallbackTimeout(sessionID)
+        const state = sessionStates.get(sessionID)
+        if (state?.pendingFallbackModel) {
+          state.pendingFallbackModel = undefined
+        }
+      }
     }
   }
 

src/hooks/runtime-fallback/constants.ts

@@ -11,7 +11,7 @@ import type { RuntimeFallbackConfig } from "../../config"
  */
 export const DEFAULT_CONFIG: Required<RuntimeFallbackConfig> = {
   enabled: true,
-  retry_on_errors: [400, 429, 503, 529],
+  retry_on_errors: [429, 500, 502, 503, 504],
   max_fallback_attempts: 3,
   cooldown_seconds: 60,
   timeout_seconds: 30,