test: convert pkg/rules tests to bdd style

Convert all 7 rules test files to use BDD-style Describe/Context/It
structure. Maintain hybrid approach with compact table-driven tests
where appropriate for efficiency.

Major improvements:
- aio_test: 292 to 62 lines (230 lines removed)
- compute_test: Consolidated into 2 focused tests
- os_test: Better organization with Windows-specific Context
- version_test: Clear Context groupings per PostgreSQL version

All 148 assertions passing.

Signed-off-by: Sebastian Webber <sebastian@swebber.me>

feat: enhance parameter docs with structured alerts

Improve readability and highlight critical information using
GitHub-style alert blocks (NOTE, TIP, WARNING, IMPORTANT). Convert
formulas to code blocks, add backticks to parameters/commands, and
reorganize recommendations for better discoverability.

Makes warnings about OOM risks, Windows limits, and security
practices more prominent and scannable.

Signed-off-by: Sebastian Webber <sebastian@swebber.me>

feat: make worker parameters dynamic based on CPU and profile

Scale worker parameters with CPU cores instead of using fixed values:
- max_worker_processes: minimum 8 or CPU count
- max_parallel_workers: minimum 8 or CPU count
- max_parallel_workers_per_gather: 2 for transactional workloads
  (Desktop/Web/Mixed/OLTP), CPU/2 for DW (analytical workloads)

Add comprehensive table-driven tests covering various CPU counts
and workload profiles.

Signed-off-by: Sebastian Webber <sebastian@swebber.me>

feat(docker): add heroku-web configuration with Dockerfile and extra …

…files

fix: os name that required lowercase

this changes the ValidOS() function that now converts the os
to lowercase before check them.

also updated the tests to use the Convey infra.

It may close #9.

Signed-off-by: Sebastian Webber <sebastian@swebber.me>

remove support go 1.21

add deploy in the release

Signed-off-by: Sebastian Webber <sebastian@swebber.me>

use --port from PORT env var

Signed-off-by: Sebastian Webber <sebastian@swebber.me>

chore: bump go to 1.19

Signed-off-by: Sebastian Webber <sebastian@swebber.me>

fix: ghcr.io and docker.io image names

Signed-off-by: Sebastian Webber <sebastian@swebber.me>