Migration guide for 0.4 #2840

Job	Run time
docs-example-check (./packages/autogen-core)	2m 28s
format	56s
docs (./packages/autogen-core)	1m 32s
lint	58s
mypy (./packages/autogen-core)	1m 55s
pyright (./packages/autogen-core)	1m 14s
mypy (./packages/autogen-magentic-one)	1m 20s
pyright (./packages/autogen-magentic-one)	58s
test (./packages/autogen-core)	59s
mypy (./packages/agbench)	55s
mypy (./packages/autogen-ext)	1m 49s
test (./packages/autogen-magentic-one)	1m 32s
pyright (./packages/agbench)	51s
mypy (./packages/autogen-agentchat)	1m 3s
test (./packages/autogen-ext)	2m 47s
pyright (./packages/autogen-ext)	1m 11s
pyright (./packages/autogen-agentchat)	1m 5s
test (./packages/autogen-agentchat)	59s
check-proto-changes-python	1m 18s
markdown-code-lint	1m 39s
	27m 29s

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