Fix SITREP browser checks for supported fallback data

[erinepshovel-code]

Post-merge review of #66 found that the browser fixture hard-coded the live 11-project count even though refresh:sitrep deliberately supports a committed last-known-good fallback that may contain a different project count.

This keeps the browser test at its declared presentation boundary: it now requires a non-empty rendered project set and exact navigation/card agreement, while tests/sitrep.test.mjs remains the contract that verifies the explicit 11-member core graph in the generator source.

Small scope: one Playwright fixture only; no authority, portfolio membership, refresh, or fallback semantics changed.

hmmm: a fallback snapshot may legitimately lag live portfolio membership; fallback=true keeps that incompletion visible.

[chatgpt-codex-connector]

Codex Review Summary

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Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-09-07T12:39:37.742156Z	9d089d2	PR opened

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