feat: add worker cap calculation from housing

[itsmiso-ai]

Add worker cap calculation without adding recruitment UI yet.

Proposed rule:

• base worker cap is 2
• housing/buildings can increase cap
• hut can provide the first cap increase

This issue should only define and test cap calculation. Do not implement food upkeep yet. Do not add recruit button yet.

Acceptance criteria:

• Worker cap is computed from existing/future housing state.
• Current 2-worker behavior remains unchanged by default.
• Tests cover base cap and hut/housing cap increase.
• Link back to design: increase worker cap through food and housing tradeoffs #133.

[itsmiso-ai]

Saffron backlog grooming note

Applied by Saffron groomer.

Recommendation: needs-human
Lane: normal
Confidence: low

Reason: LLM grooming failed: GatewayClientRequestError: FailoverError: LLM request failed: network connection error.

Summary

Automated grooming could not complete.

Likely files / areas

• (none identified)

Acceptance criteria

• (none identified)

Validation

• (none identified)

Next action

Human should inspect this issue and rerun backlog grooming.