chore: Update README.md (#46)

## Summary

Update both README.md and DEVELOPMENT.md with the coverage and
benchmarks sections.

.github/workflows/coverage-and-benchmark.yml

@@ -8,7 +8,7 @@ permissions:
   contents: write
 jobs:
   test:
-    name: Run unit tests
+    name: Run coverage and benchmark
     runs-on: ubuntu-latest
     steps:
       - name: Check out code

README.md

@@ -14,7 +14,7 @@ It also allows writing self-documenting validation rules through a
 
 **GO** **V**alidate **Y**ourself!
 
-**DISCLAIMER** govy is in active development, while the core API is unlikely
+**DISCLAIMER**: govy is in active development, while the core API is unlikely
 to change, breaking changes may be introduced with new versions until v1
 is released. Checkout [roadmap](./docs/ROADMAP.md) for upcoming,
 planned features.
@@ -39,6 +39,8 @@ planned features.
     1. [Reflection](#reflection)
     2. [Trivia](#trivia)
 5. [Development](#development)
+    1. [Tests coverage](#tests-coverage)
+    2. [Benchmarks](#benchmarks)
 6. [Acknowledgments](#acknowledgments)
 
 ## Getting started
@@ -613,6 +615,19 @@ with them, and the idea for `govy` was born.
 Checkout both [contributing guidelines](./docs/CONTRIBUTING.md) and
 [development instructions](./docs/DEVELOPMENT.md).
 
+### Tests coverage
+
+Tests coverage HTML for current `main` branch state can be inspected
+[here](https://raw.githack.com/wiki/nobl9/govy/coverage.html).
+
+Note that `cmd` package is tested by building and running Go binaries directly.
+This means there won't be any coverage for some of the core functions there.
+
+### Benchmarks
+
+Benchmarks' history is collected and can be viewed as charts over time
+[here](https://nobl9.github.io/govy/dev/bench/).
+
 ## Acknowledgments
 
 The API along with the accompanying nomenclature was heavily inspired by the

docs/DEVELOPMENT.md

@@ -74,3 +74,25 @@ Refer to this [README.md](../internal/validation/README.md) for more information
 Renovate is configured to automatically merge minor and patch updates.
 For major versions, which sadly includes GitHub Actions, manual approval
 is required.
+
+## Tests coverage
+
+Tests coverage reporting is automated using the following actions:
+- [go-coverage-report](https://github.com/ncruces/go-coverage-report) which
+  is responsible for updating the coverage badge in main README.md.
+  It stores the coverage results in GitHub wiki and it can be easily inspected
+  [here](https://raw.githack.com/wiki/nobl9/govy/coverage.html).
+  This action is run only on `push` events to _main_ branch.
+- [coverdiff](https://github.com/kskitek/coverdiff) which is executed on each
+  PR runs the tests coverage and posts a summary report as a comment.
+  It highlights positive and negative changes.
+
+## Benchmarks
+
+[github-action-benchmark](https://github.com/benchmark-action/github-action-benchmark)
+is used to collect and store benchmarks' results.
+It inspects PRs and if a configured threshold difference between previous
+and current results is breached it will leave a comment on the affected PR.
+
+On top of that it publishes benchmarks' history charts onto
+[GitHub Pages](https://nobl9.github.io/govy/dev/bench).