fix(schema)!: Split out indiivual event structs

[epage]

This makes things more composable if someone wants to emit their own messages.

[coveralls]

Pull Request Test Coverage Report for Build 16999101112

Details

• 0 of 225 (0.0%) changed or added relevant lines in 6 files are covered.
• 6 unchanged lines in 5 files lost coverage.
• Overall coverage decreased (-1.4%) to 33.655%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
crates/libtest-json/tests/roundtrip.rs	0	2	0.0%
crates/libtest2-harness/src/notify/summary.rs	0	6	0.0%
crates/libtest2-harness/src/notify/pretty.rs	0	16	0.0%
crates/libtest2-harness/src/notify/terse.rs	0	18	0.0%
crates/libtest2-harness/src/harness.rs	0	42	0.0%
crates/libtest-json/src/event.rs	0	141	0.0%

Files with Coverage Reduction	New Missed Lines	%
crates/libtest2-harness/src/harness.rs	1	0.0%
crates/libtest2-harness/src/notify/summary.rs	1	0.0%
crates/libtest2-harness/src/notify/terse.rs	1	0.0%
crates/libtest-json/src/event.rs	1	0.0%
crates/libtest2-harness/src/notify/pretty.rs	2	0.0%

Totals
Change from base Build 16998323895:	-1.4%
Covered Lines:	488
Relevant Lines:	1450

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💛 - Coveralls