docs: AGENTS.md as canonical repo guide; CLAUDE.md points to it

[Kukks]

Make AGENTS.md the canonical repo guide

CLAUDE.md was gitignored (local-only) and AGENTS.md was stale. This makes AGENTS.md the single source of truth and turns CLAUDE.md into a tracked one-line pointer to it, so every agent/tool reads the same guide.

Changes

• .gitignore: stop ignoring CLAUDE.md (kept .claude/ ignored).
• CLAUDE.md: now a one-line pointer to AGENTS.md (tracked).
• AGENTS.md:
  • Folded in the version-bump rules previously only in the local CLAUDE.md.
  • Fixed inaccuracies:
    • "Everything targets .NET 8" → plugin + tests target .NET 10; NNark SDK libs target .NET 8 (verified via setup.sh DEBUG_PLUGINS net10.0 path + csproj TFMs).
    • Structure rewritten to the real layout: BTCPayServer.Plugins.ArkPayServer, submodules/NNark (NArk.Core/NArk.Abstractions/NArk.Swaps/NArk.Storage.EfCore), submodules/btcpayserver, NArk.E2E.Tests, NArk.sln. Removed the non-existent NArk, NArk.Grpc (Protos/ark/v1), and NArk/Boltz projects.
    • Dropped the "early-stage implementation / most components not yet built" framing — the plugin ships Ark-native, Boltz Lightning (submarine + reverse), boarding, and Arkade asset-acceptance flows. Future-tense ("will integrate") changed to present where now true.
    • Setup section corrected to what setup.sh actually does (+ start-test-env.cmd).
  • Conceptual / Ark / Arkade / design sections preserved (still accurate).

Docs-only; no code changes. Separate from the asset PR (#55) per request.

[arkanaai]

✅ Docs-only — LGTM

Verified every factual claim against the repo:

• TFMs: Plugin + E2E tests → net10.0 ✔︎, NNark SDK libs (NArk.Core, NArk.Abstractions, NArk.Swaps, NArk.Storage.EfCore) → net8.0 ✔︎
• Structure: All listed projects exist. Old phantom entries (NArk, NArk.Grpc, NArk/Boltz) correctly removed.
• setup.sh: Submodules → workloads → DEBUG_PLUGINS appsettings → publish. Matches description. start-test-env.cmd exists.
• NArk.E2E.Tests: Present at root, not in NArk.sln — consistent with "runs in the e2e CI workflow" note.
• .gitignore: Removing CLAUDE.md from ignore makes sense now that it's a tracked one-line pointer.
• CLAUDE.md: Single-line redirect to AGENTS.md — clean canonical-source pattern.
• Version-bump rules: Folded into AGENTS.md so they're not lost in a gitignored file. Good.
• Tense fixes ("will integrate" → "integrates", dropping "early-stage" framing): Accurate — the plugin ships these flows today.

No protocol-critical changes. No code changes. No cross-repo impact.

One minor nit (non-blocking): AGENTS.md:4 says "NNark SDK libraries" but the submodule directory and all project names use NArk.*. The repo name on GitHub is arkade-os/dotnet-sdk and the directory is submodules/NNark. Might be worth a parenthetical clarifying that "NNark" is the submodule/repo name while NArk.* are the .NET project names, to avoid confusion for new contributors. Take it or leave it.

🤖 Reviewed by Arkana