refactor: ingestion data flow

[de-sh]

Fixes #XXXX.

Description

Rids code of unnecessary conversions and copying

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This PR has:

• been tested to ensure log ingestion and log query works.
• added comments explaining the "why" and the intent of the code wherever would not be obvious for an unfamiliar reader.
• added documentation for new or modified features or behaviors.

[coveralls]

Pull Request Test Coverage Report for Build 12906543338

Details

• 83 of 442 (18.78%) changed or added relevant lines in 28 files are covered.
• 12 unchanged lines in 8 files lost coverage.
• Overall coverage increased (+0.1%) to 12.856%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
src/catalog/mod.rs	0	1	0.0%
src/kafka.rs	0	1	0.0%
src/metadata.rs	0	1	0.0%
src/handlers/http/modal/query/querier_ingest.rs	0	2	0.0%
src/event/writer/mem_writer.rs	0	3	0.0%
src/handlers/http/kinesis.rs	0	4	0.0%
src/handlers/http/modal/query/querier_role.rs	0	4	0.0%
src/handlers/http/role.rs	0	4	0.0%
src/handlers/http/modal/ingest/ingestor_role.rs	0	5	0.0%
src/validator.rs	0	5	0.0%

Files with Coverage Reduction	New Missed Lines	%
src/handlers/http/modal/utils/ingest_utils.rs	1	28.89%
src/otel/traces.rs	1	0.0%
src/handlers/http/modal/query/querier_ingest.rs	1	0.0%
src/event/writer/mod.rs	1	0.0%
src/event/mod.rs	1	0.0%
src/handlers/http/ingest.rs	1	67.23%
src/handlers/http/logstream.rs	2	1.68%
src/storage/mod.rs	4	0.0%

Totals
Change from base Build 12873819985:	0.1%
Covered Lines:	2477
Relevant Lines:	19268

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💛 - Coveralls

[nikhilsinhaparseable]

good to merge