integrate semble/cosmik as phi's public memory layer

two changes:

1. personality file: new memory section explaining the difference
between private memory (recall/note — what phi knows for itself)
and public memory (cosmik cards, collections, connections via
semble — what phi contributes to the shared knowledge layer).
search_network vs recall answer different questions.

2. agent.py: new inject_public_memory dynamic system prompt that
fetches phi's own cosmik state (collections + recent cards) from
the PDS and injects it into context. phi now sees what it has
already curated publicly without having to search_network for
its own records. this lets phi decide whether to add new cards,
update collections, or draw connections based on what it already
has vs what's new.

phi was already actively curating 10 cards, 6 collections, and 10
connections on semble — but nothing in the system prompt told it
these existed or what they were for. the one-line mention in the
old operational instructions ("you can also create public records")
gave no context about why or when to use them.