Make the celeris, loadgen, probatorium and docs READMEs attractive for visitors: consistent live badges (Codecov, CodSpeed, Scorecard; drop Go Report Card and stale tier badges) and a stronger first screen

[FumingPower3925]

Make the READMEs of all four public repos attractive and trustworthy for first-time visitors: celeris, loadgen, probatorium and docs. This is the presentation half. #414 stays the release-data half: regenerating the benchmark hero and headline numbers from the v1.6.0 bench, and correcting the stale arm64 and SIMD claims. The two should land together before the v1.6.0 announcement.

What is there today (read 2026-09-26)

repo	badges now	problems
celeris	CI, Nightly Validation, Weekend Soak (both probatorium tiers), Go Reference, Go Report Card, License	The Go Report Card badge is to be removed. The two tier badges report the last run of workflows whose schedules have been paused since probatorium#380; Weekend Soak's last runs failed, so a visitor sees a red badge that says nothing about the code today.
loadgen	Go Reference, CI, License	No coverage or benchmark signal.
probatorium	Nightly Validation, Weekend Soak, Test, Lint, License	Same stale-tier-badge problem.
docs	site, License, "Astro 5", "Bun ≥1.3" (HTML badges)	"Astro 5" is stale: the site runs Astro 7.3. The style differs from the other three.

All four already have a cover image (.github/cover.png).

Badges: one consistent row per repo, and only ones that are true and live

• Remove: Go Report Card (celeris).
• Add where it applies, now that add CodeRabbit, CodSpeed and Codecov #690 installs the services:
  • Codecov coverage, on all four: https://codecov.io/gh/goceleris/<repo>/graph/badge.svg, linking to the Codecov page. Add it only after main has a first upload.
  • CodSpeed, on celeris and loadgen (the repos with benchmarks): https://img.shields.io/endpoint?url=https://codspeed.io/badge.json, linking to the repo's CodSpeed page. Add it once main has a macro-runner baseline.
  • OpenSSF Scorecard, on celeris (it already runs the Scorecard workflow): https://api.scorecard.dev/projects/github.com/goceleris/celeris/badge.
  • Latest release and Go version from go.mod (shields.io) for the Go repos.
  • CI for each repo's own required workflow.
• Validation-tier badges: keep them only if they reflect a run that is actually scheduled or recent. Otherwise replace them with a link to the latest validation report, or bring them back when the tiers run on a cadence again.
• Use one style across the four repos: a centered row under the cover, with badges grouped as status → quality → project.

Content: what a visitor needs in the first screen

• celeris:
  • A one-sentence pitch and a 10-line quick start that compiles against the released module.
  • The benchmark hero from Refresh README and docs for the current release #414, and 4-6 feature highlights. Every claim must be verifiable in the code or the published data: no SIMD claim while no SIMD path is used (Exercise the arm64 NEON header parser in CI #424), and the arm64 story must be current.
  • Links to the docs site, pkg.go.dev, the validation methodology (probatorium) and CONTRIBUTING.
• loadgen: what it is for, one install-and-run example, the headline properties (allocation, HTTP/1.1 and HTTP/2, latency correctness), and how celeris uses it.
• probatorium: what it proves and how (tiers, invariants, arm64 + x86 cluster), where the latest results live, and how to reproduce a run.
• docs: what the site is, how to run it locally (bun install && bun run dev), and the current stack versions, read from package.json rather than hard-coded.
• All four:
  • Consistent headings and working relative links.
  • Alt text on every image.
  • A short "Related projects" footer linking the other three.

Acceptance criteria

• celeris README updated; Go Report Card gone; badge row consistent and all green or neutral on the day it merges
• loadgen README updated
• probatorium README updated
• docs README updated (stale "Astro 5" fixed)
• Every badge renders, links somewhere useful, and reflects something that runs today; no stale status
• Every factual claim is checked against code or published data, with the check noted in the PR
• Rendered on GitHub in light and dark mode, and on a phone-width viewport, before merging

Depends on: #690 (the Codecov and CodSpeed badges need first uploads on main), and pairs with #414.

[FumingPower3925]

Three of the four READMEs are done and merged:

repo	PR	merge	badges (value on the day)
loadgen	goceleris/loadgen#84	a89f02d	CI passing, Codecov 75%, CodSpeed, Go Reference, release v1.4.13, Go v1.27.0, Apache-2.0
docs	goceleris/docs#75	ae6b949	CI passing, site up, Codecov 91%, astro ^7.3.3 and bun >=1.3.0 (both read live from package.json), Apache-2.0
probatorium	goceleris/probatorium#417	6f5521c	Test and Lint passing, Codecov 65%, Go v1.27.0, Apache-2.0. The paused tier badges are replaced by a "where the latest results live" section

Each PR body has a claims table (claim → where it was verified); about 20 loadgen claims and a dozen probatorium claims were wrong and are corrected. Every badge URL returned 200 with an SVG, and every link resolved. Before merging, each README was looked at on GitHub in light and dark mode on desktop, and at 375 px wide: no horizontal overflow, and every image has alt text.

What is left for this issue is the celeris README. It follows the merges of #699 (the Codecov and CodSpeed baselines on main) and #694/#697 (which edit README.md), and pairs with #414's v1.6.0 bench numbers.

Defects the verification found in passing (in loadgen's HTTP/2 client and -close mode, probatorium's BenchTier ETA, mage Fuzz, and one docs results/README description) are being reproduced and filed separately.