[SAOC 2024] Improve D Error Messages - Weekly Update #16

[Royal Simpson Pinto]

## Summary of Progress (December 30 – January 5)

This week, I enabled `verrors=context` globally for users without 
making any changes to the test files. I also started looking into 
tasks in the bug tracker related to `opDispatch` error messages 
and am waiting for inputs on the planned error 
documentation/website.

### What I Worked On

PR: feat(errors): enable verrors=context globally - 
[#20576](https://github.com/dlang/dmd/pull/20576)

- Cleared CI after resolving issues with `COMPILE` and `RUN` test 
files.
- Fixed a FreeBSD-specific complaint about a backslash to ensure 
compatibility.
- Adjusted `COMPILE` and `RUN` test files manually, as the global 
change affects deprecations. The approach ensures deprecations 
continue to run with `-dw` (deprecations as warnings, default) 
instead of `-de` (deprecations as errors).

**Exploring Bug Tracker/GitHub Issues for tasks**
- While awaiting inputs for the planned error 
documentation/website, I started reviewing the bug tracker for 
tasks.
   - Currently looking into issues with `opDispatch` error 
messages for potential fixes.

### Next Steps

1. Investigate and address `opDispatch` error message bugs.
2. Finalize plans for the error documentation/website after 
receiving mentor inputs.