This commit applies the new canonical formatting style using `clang-format` with custom settings (notably 4-space indentation), as part of our shift toward automated formatting normalization.
⚠️ No functional changes are included — only whitespace and layout modifications as produced by `clang-format`.
This change is part of the formatting modernization strategy discussed in:
https://github.com/rsyslog/rsyslog/issues/5747
Key context:
- Formatting is now treated as a disposable view, normalized via tooling.
- The `.clang-format` file defines the canonical style.
- A fixup script (`devtools/format-code.sh`) handles remaining edge cases.
- Formatting commits are added to `.git-blame-ignore-revs` to reduce noise.
- Developers remain free to format code however they prefer locally.
The zstd library provides better and faster compression than zlib.
This patch integrates zstd as a dynamically-loadable functionality.
As such, no further dependencies need to be added to the rsyslog
base package.
Due to the increased performance, usage of zstd is highly recommended
for high-volume use cases.
This patch also refactor zlib compression in order to unify handling
in both compression cases.
