fix: resolve 25 pre-publish blockers

- postinstall.mjs: fix alias package detection
- migrate-legacy-plugin-entry: dedupe + regression tests
- task_system: default consistency across runtime paths
- task() contract: consistent tool behavior
- runtime model selection, tool cap, stale-task cancellation
- recovery sanitization, context-limit gating
- Ralph semantic DONE hardening, Atlas fallback persistence
- native-skill description/content, skill path traversal guard
- publish workflow: platform awaited via reusable workflow job
- release: version edits reapplied before commit/tag
- JSONC plugin migration: top-level plugin key safety
- cold-cache: user fallback models skip disconnected providers
- docs/version/release framing updates

Verified: bun test (4599 pass), tsc --noEmit clean, bun run build clean

src/plugin-handlers/agent-config-handler.test.ts

@@ -290,7 +290,7 @@ describe("applyAgentConfig builtin override protection", () => {
     })
 
     // then
-    expect(createSisyphusJuniorAgentSpy).toHaveBeenCalledWith(undefined, "openai/gpt-5.4", false)
+    expect(createSisyphusJuniorAgentSpy).toHaveBeenCalledWith(undefined, "openai/gpt-5.4", true)
   })
 
   test("includes project and global .agents skills in builtin agent awareness", async () => {