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/features/background-agent/manager.test.ts

@@ -3312,6 +3312,9 @@ describe("BackgroundManager.checkAndInterruptStaleTasks", () => {
         prompt: async () => ({}),
         promptAsync: async () => ({}),
         abort: async () => ({}),
+        get: async () => {
+          throw new Error("missing")
+        },
       },
     }
     const manager = new BackgroundManager({ client, directory: tmpdir() } as unknown as PluginInput, { staleTimeoutMs: 180_000 })
@@ -3348,6 +3351,9 @@ describe("BackgroundManager.checkAndInterruptStaleTasks", () => {
         prompt: async () => ({}),
         promptAsync: async () => ({}),
         abort: async () => ({}),
+        get: async () => {
+          throw new Error("missing")
+        },
       },
     }
     const manager = new BackgroundManager({ client, directory: tmpdir() } as unknown as PluginInput, { staleTimeoutMs: 180_000 })
@@ -3437,6 +3443,7 @@ describe("BackgroundManager.checkAndInterruptStaleTasks", () => {
       status: "running",
       startedAt: new Date(Date.now() - 15 * 60 * 1000),
       progress: undefined,
+      consecutiveMissedPolls: 2,
     }
 
     getTaskMap(manager).set(task.id, task)
@@ -3471,6 +3478,7 @@ describe("BackgroundManager.checkAndInterruptStaleTasks", () => {
       status: "running",
       startedAt: new Date(Date.now() - 15 * 60 * 1000),
       progress: undefined,
+      consecutiveMissedPolls: 2,
     }
 
     getTaskMap(manager).set(task.id, task)