docs: update AssistantAgent documentation with a new figure, attentio… #35

Job	Run time
check-proto-changes-python	1m 10s
docs-example-check (./packages/autogen-core)	2m 49s
docs (./packages/autogen-core)	1m 37s
format	54s
lint	52s
markdown-code-lint	2m 11s
mypy (./packages/autogen-core)	2m 22s
pyright (./packages/autogen-core)	1m 8s
pyright (./packages/autogen-magentic-one)	1m 5s
samples-code-check	57s
mypy (./packages/autogen-magentic-one)	1m 39s
pyright (./packages/agbench)	57s
mypy (./packages/agbench)	1m 0s
pyright (./packages/autogen-ext)	1m 4s
mypy (./packages/autogen-ext)	2m 12s
test (./packages/autogen-core)	1m 0s
mypy (./packages/autogen-agentchat)	1m 25s
pyright (./packages/autogen-agentchat)	1m 0s
test (./packages/autogen-magentic-one)	1m 50s
mypy (./packages/magentic-one-cli)	1m 23s
test (./packages/autogen-ext)	3m 56s
pyright (./packages/magentic-one-cli)	56s
test (./packages/autogen-agentchat)	1m 45s
codecov (./packages/autogen-core)	11s
codecov (./packages/autogen-magentic-one)	7s
codecov (./packages/autogen-ext)	13s
codecov (./packages/autogen-agentchat)	8s
	35m 51s

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