ci: consolidate remaining 10 workflows into ci.yaml

Add all non-required-check E2E workflows and prek lint to the
consolidated ci.yaml:

- 4 standard Python E2Es (async, benchmark, coverage, init)
- 3 JS E2Es (cjs-function, esm-async, ts-class)
- 2 Java E2Es (fibonacci-nogit, tracer)
- prek lint

New change detection outputs:
- e2e_js: triggers JS E2Es when packages/ changes
- e2e_java: triggers Java E2Es when java runtime/fixtures change

Total: 17 jobs + determine-changes + gate = 19 jobs in one file.
Down from 22 workflow files to 7 (remaining are non-test: claude,
codeflash self-optimize, label-workflow-changes, publish, java-e2e).

Additional savings per irrelevant PR: ~$0.80 (10 jobs x ~$0.08).
Total per skipped PR: ~$1.85.

Author: KRRT7