New Concept Exercise: Freelancer Rates

[marianfoo]

This completes the existing draft for the Freelancer Rates concept exercise.

Summary

• Added the missing numbers and arithmetic-operators concept documentation.
• Updated config.json so both new concepts are registered and the learning path keeps lasagna before freelancer-rates.
• Kept freelancer-rates as wip because configlet does not allow it to be user-facing while its basics prerequisite is only taught by the wip Lasagna exercise.
• Reworked the exercise docs, hints, design notes, student stub, exemplar, and tests for ABAP.
• Fixed the stale test expectations against the current canonical exercise behavior:
  • days_in_budget rounds down to a whole number.
  • monthly-discount prices round up to the canonical expected values.
  • day-rate decimal precision is not rounded away.

Source and history

The exercise is ported from the current JavaScript concept exercise:
https://github.com/exercism/javascript/tree/main/exercises/concept/freelancer-rates

PR history reviewed:

• Original PR opened in 2022 from marianfoo:concept-freelancer-rates.
• Later branch updates in 2022, 2023, and 2024 kept it mergeable.
• The 2024 comment noted that the missing concepts were still not added.
• GitHub search found no other open or closed ABAP PR implementing Freelancer Rates.

Validation

• ./bin/configlet lint
• npx -y @abaplint/cli@2.119.27 abaplint.json
• npx -y @abaplint/cli@2.119.27 abaplint_solutions.json
• ./bin/configlet sync --exercise freelancer-rates --filepaths --metadata --docs --tests include
• Targeted Docker runner for freelancer-rates: 12/12 tests passed.
• SAP arc-1 syntax check against ABAP release 758: passed for the final exemplar plus test class.

Standards cross-check:

• freelancer-rates has the same concept exercise file layout as lasagna.
• numbers and arithmetic-operators have the same concept documentation file layout as basics.
• All new Markdown files start with the expected top-level headings.
• The package/class abapGit XML files match the conventions used by the other exercises; the package description follows the dominant Exercism: <Name> pattern.

I also attempted a full-track bin/test run in a temporary copy on macOS after removing the GNU /usr/bin/time -f wrapper from that temp copy. It checked 50 exercise blocks; 36 passed. The failures were outside this PR, mostly from duplicate *.clas 2.abap files created only in the temporary copy and one existing collatz-conjecture exemplar issue. The actual checkout has no * 2* files.

[mbtools]

A little progress, but I don't have time to add the missing concepts. Oh well, someday

[marianfoo]

Can anyone review so this PR can be finally merged :D

[mbtools]

LGTM 👍

[marianfoo]

Cheers!