fix: resolve 3 community-reported bugs (#2915, #2917, #2918)

- background_output: snapshot read cursor before consuming, restore on
  /undo message removal so re-reads return data (fixes #2915)
- MCP loader: preserve oauth field in transformMcpServer, add scope/
  projectPath filtering so local-scoped MCPs only load in matching
  directories (fixes #2917)
- runtime-fallback: add 'reached your usage limit' to retryable error
  patterns so quota exhaustion triggers model fallback (fixes #2918)

Verified: bun test (4606 pass / 0 fail), tsc --noEmit clean

src/features/claude-code-plugin-loader/mcp-server-loader.test.ts

@@ -0,0 +1,76 @@
+import { afterEach, beforeEach, describe, expect, it, mock } from "bun:test"
+import { mkdirSync, rmSync, writeFileSync } from "fs"
+import { tmpdir } from "os"
+import { join } from "path"
+import type { LoadedPlugin } from "./types"
+
+const TEST_DIR = join(tmpdir(), `plugin-mcp-loader-test-${Date.now()}`)
+const PROJECT_DIR = join(TEST_DIR, "project")
+const PLUGIN_DIR = join(TEST_DIR, "plugin")
+const MCP_CONFIG_PATH = join(PLUGIN_DIR, "mcp.json")
+
+describe("loadPluginMcpServers", () => {
+  beforeEach(() => {
+    mkdirSync(PROJECT_DIR, { recursive: true })
+    mkdirSync(PLUGIN_DIR, { recursive: true })
+    mock.module("../../shared/logger", () => ({
+      log: () => {},
+    }))
+  })
+
+  afterEach(() => {
+    mock.restore()
+    rmSync(TEST_DIR, { recursive: true, force: true })
+  })
+
+  describe("#given plugin MCP entries with local scope metadata", () => {
+    it("#when loading plugin MCP servers #then only entries matching the current cwd are included", async () => {
+      writeFileSync(
+        MCP_CONFIG_PATH,
+        JSON.stringify({
+          mcpServers: {
+            globalServer: {
+              command: "npx",
+              args: ["global-plugin-server"],
+            },
+            matchingLocal: {
+              command: "npx",
+              args: ["matching-plugin-local"],
+              scope: "local",
+              projectPath: PROJECT_DIR,
+            },
+            nonMatchingLocal: {
+              command: "npx",
+              args: ["non-matching-plugin-local"],
+              scope: "local",
+              projectPath: join(PROJECT_DIR, "other-project"),
+            },
+          },
+        })
+      )
+
+      const plugin: LoadedPlugin = {
+        name: "demo-plugin",
+        version: "1.0.0",
+        scope: "project",
+        installPath: PLUGIN_DIR,
+        pluginKey: "demo-plugin@test",
+        mcpPath: MCP_CONFIG_PATH,
+      }
+
+      const originalCwd = process.cwd()
+      process.chdir(PROJECT_DIR)
+
+      try {
+        const { loadPluginMcpServers } = await import("./mcp-server-loader")
+        const servers = await loadPluginMcpServers([plugin])
+
+        expect(servers).toHaveProperty("demo-plugin:globalServer")
+        expect(servers).toHaveProperty("demo-plugin:matchingLocal")
+        expect(servers).not.toHaveProperty("demo-plugin:nonMatchingLocal")
+      } finally {
+        process.chdir(originalCwd)
+      }
+    })
+  })
+})

src/features/claude-code-plugin-loader/mcp-server-loader.ts

@@ -1,6 +1,7 @@
 import { existsSync } from "fs"
 import type { McpServerConfig } from "../claude-code-mcp-loader/types"
 import { expandEnvVarsInObject } from "../claude-code-mcp-loader/env-expander"
+import { shouldLoadMcpServer } from "../claude-code-mcp-loader/scope-filter"
 import { transformMcpServer } from "../claude-code-mcp-loader/transformer"
 import type { ClaudeCodeMcpConfig } from "../claude-code-mcp-loader/types"
 import { log } from "../../shared/logger"
@@ -11,6 +12,7 @@ export async function loadPluginMcpServers(
   plugins: LoadedPlugin[],
 ): Promise<Record<string, McpServerConfig>> {
   const servers: Record<string, McpServerConfig> = {}
+  const cwd = process.cwd()
 
   for (const plugin of plugins) {
     if (!plugin.mcpPath || !existsSync(plugin.mcpPath)) continue
@@ -25,6 +27,15 @@ export async function loadPluginMcpServers(
       if (!config.mcpServers) continue
 
       for (const [name, serverConfig] of Object.entries(config.mcpServers)) {
+        if (!shouldLoadMcpServer(serverConfig, cwd)) {
+          log(`Skipping local plugin MCP server "${name}" outside current cwd`, {
+            path: plugin.mcpPath,
+            projectPath: serverConfig.projectPath,
+            cwd,
+          })
+          continue
+        }
+
         if (serverConfig.disabled) {
           log(`Skipping disabled MCP server "${name}" from plugin ${plugin.name}`)
           continue