feat(prompts): require lint alongside tests and typecheck in agent instructions

Every agent-facing quality gate that used to pair tests with typecheck now
also includes lint. Specifically:

- core/src/types.ts: QA Check skill prompt runs lint, tests, typecheck (was
  tests only) and gates task_done() on all three.
- core/src/agent-prompts.ts + engine/src/reviewer.ts: "Do NOT issue REVISE"
  exclusion list now covers lint as well, so out-of-scope fixes that
  restore lint remain allowed (matches the already-lint-aware completion
  gate text at the top of the same prompts).
- engine/src/executor.ts: task_done() pre-flight checklist adds an explicit
  "if the repo has a lint command, run it and fix failures" bullet, mirrors
  the typecheck bullet, and expands the CRITICAL line from "ALL test
  failures" to "ALL lint, test, and typecheck failures".
- core/src/store.ts: default Step 2 checklist (Testing & Verification) now
  includes Lint and Typecheck alongside "All tests pass".
- cli/src/commands/plugin-scaffold.ts: generated plugin README and the
  "Next steps" CLI output include \`pnpm lint\` between install and test.

Existing prompts that already paired lint with tests+typecheck (the
Completion section, hard quality gates, triage testing requirements) are
unchanged.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

packages/cli/src/commands/__tests__/daemon.test.ts

@@ -53,6 +53,7 @@ const mocks = vi.hoisted(() => {
       watch: vi.fn().mockResolvedValue(undefined),
       close: vi.fn(),
       getFusionDir: vi.fn().mockReturnValue("/repo/.fusion"),
+      getRootDir: vi.fn().mockReturnValue("/repo"),
       getMissionStore: vi.fn().mockReturnValue(missionStore),
       getSettings: vi.fn().mockResolvedValue({
         maxConcurrent: 2,

packages/cli/src/commands/plugin-scaffold.ts

@@ -154,6 +154,7 @@ fn plugin install /path/to/${name}
 
 \`\`\`bash
 pnpm install
+pnpm lint
 pnpm test
 pnpm build
 \`\`\`
@@ -220,6 +221,7 @@ export async function runPluginCreate(
   console.log("  Next steps:");
   console.log(`    cd ${targetDir}`);
   console.log("    pnpm install");
+  console.log("    pnpm lint");
   console.log("    pnpm test");
   console.log();
 }