[v2] Dispatcher/ServerRunner receive-path swap — replaces BaseSession #2415

Job	Run time
checks / pre-commit	35s
checks / readme-snippets	30s
checks / test (3.10, locked, windows-latest)	2m 35s
checks / test (3.10, lowest-direct, windows-latest)	2m 47s
checks / test (3.10, locked, ubuntu-latest)	1m 11s
checks / test (3.11, lowest-direct, windows-latest)	3m 9s
checks / test (3.14, lowest-direct, ubuntu-latest)	1m 31s
checks / test (3.10, lowest-direct, ubuntu-latest)	1m 10s
checks / test (3.11, lowest-direct, ubuntu-latest)	1m 4s
checks / test (3.13, locked, windows-latest)	3m 3s
checks / test (3.13, lowest-direct, ubuntu-latest)	1m 11s
checks / test (3.12, locked, ubuntu-latest)	1m 10s
checks / test (3.11, locked, windows-latest)	2m 45s
checks / test (3.14, lowest-direct, windows-latest)	1m 49s
checks / test (3.12, locked, windows-latest)	4m 1s
checks / test (3.12, lowest-direct, ubuntu-latest)	1m 12s
checks / test (3.14, locked, ubuntu-latest)	2m 6s
checks / test (3.11, locked, ubuntu-latest)	58s
checks / test (3.12, lowest-direct, windows-latest)	3m 31s
checks / test (3.13, lowest-direct, windows-latest)	3m 14s
checks / test (3.14, locked, windows-latest)	4m 7s
checks / test (3.13, locked, ubuntu-latest)	1m 1s
all-green	2s
	44m 42s

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