chore(hook): route complex tasks through swarm-worker in UserPromptSubmit reminder

[acreeger]

Summary

• Swarm-completed UserPromptSubmit reminder: kept the prose tight ("Do not ask analysis agent to implement fixes") and folded the new routing into the table — "New features / complex changes" goes through a child issue + `@agent-iloom-swarm-worker`, and a new "Multiple issues at once" row says spawn ONE agent team with multiple parallel `@agent-iloom-swarm-worker` workers.
• Non-swarm UserPromptSubmit reminder: added the same "Do not ask analysis agent to implement fixes" warning.

Test plan

• Manual: in a swarm session post-completion, submit a prompt and verify the additionalContext shows the updated table
• Manual: in a regular session, submit a prompt and verify the analyzer warning is now in the preamble