feat: implement OTEL mcp.server.* metrics #1776

Job	Run time
checks / readme-snippets	11s
checks / pre-commit	33s
checks / test (3.11, lowest-direct, windows-latest)	1m 10s
checks / test (3.12, locked, windows-latest)	3m 7s
checks / test (3.10, locked, windows-latest)	2m 41s
checks / test (3.10, locked, ubuntu-latest)	55s
checks / test (3.11, locked, ubuntu-latest)	50s
checks / test (3.10, lowest-direct, windows-latest)	1m 4s
checks / test (3.11, locked, windows-latest)	3m 10s
checks / test (3.13, locked, windows-latest)	2m 21s
checks / test (3.12, lowest-direct, windows-latest)	1m 12s
checks / test (3.12, lowest-direct, ubuntu-latest)	42s
checks / test (3.11, lowest-direct, ubuntu-latest)	35s
checks / test (3.13, locked, ubuntu-latest)	50s
checks / test (3.14, locked, windows-latest)	3m 40s
checks / test (3.14, lowest-direct, windows-latest)	1m 9s
checks / test (3.14, locked, ubuntu-latest)	2m 18s
checks / test (3.13, lowest-direct, windows-latest)	1m 12s
checks / test (3.10, lowest-direct, ubuntu-latest)	33s
checks / test (3.12, locked, ubuntu-latest)	54s
checks / test (3.13, lowest-direct, ubuntu-latest)	35s
checks / test (3.14, lowest-direct, ubuntu-latest)	25s
all-green	2s
	30m 9s

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