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/write-existing-file-guard/index.test.ts

@@ -532,13 +532,16 @@ describe("createWriteExistingFileGuardHook", () => {
       })
     ).resolves.toBeDefined()
 
-    // delete the session to trigger cleanup of any stored permissions/state
+    // read the file again to re-establish permission after first write consumed it
     await invoke({
-      tool: "session.deleted",
+      tool: "read",
       sessionID,
-      outputArgs: {},
+      outputArgs: { filePath: existingFile },
     })
 
+    // delete the session to trigger cleanup of any stored permissions/state
+    await emitSessionDeleted(sessionID)
+
     // after session deletion, the previous permissions must no longer apply
     await expect(
       invoke({