docs: scrub GitHub-specifics after Gitea migration; add tea issue conventions

- Cargo.toml: repository -> git.lazyeval.net/oli/rdbms-playground
- requirements.md: backlog now tracked as Gitea issues
- ADR-0001 Amendment 1: distribution channel reopened post-migration
  (Decision text preserved per supersede-don't-rewrite)
- CLAUDE.md: issue-tracking working method + Gitea/tea operational section

docs/adr/0001-language-and-tui-framework.md

@@ -45,3 +45,25 @@ package managers (`cargo binstall`, Homebrew, Scoop, `winget`).
 - TUI styling will require explicit work to match the polish that
   Bubble Tea / Lipgloss give for free; budget for it in the design
   pass.
+
+## Amendment 1 — Distribution channel is open after the Gitea migration (2026-06-09)
+
+The *Decision* block above assumed prebuilt binaries would ship "via
+GitHub releases plus package managers." Since then the repository has
+been migrated off GitHub to a self-hosted Gitea instance
+(`git.lazyeval.net/oli/rdbms-playground`), and `tea` is the forge CLI
+in use. The "GitHub releases" half of that sentence is therefore no
+longer a settled assumption.
+
+This amendment does **not** pick a replacement. Binary distribution is
+not built yet (no release pipeline, no CI — `requirements.md` TT5/E*
+remain open), so the channel for prebuilt binaries is an **open
+choice** — Gitea releases, a GitHub mirror's releases, or both — to be
+settled by a dedicated ADR when distribution is actually implemented.
+The package-manager channels named in the Decision (`cargo binstall`,
+Homebrew, Scoop, `winget`) are independent of the forge and are
+unaffected.
+
+(For the same supersede-don't-rewrite reason, the Decision block also
+still names `sqlparser-rs`, which ADRs 0030–0036 replaced with a
+hand-rolled grammar; that is recorded there, not by editing this ADR.)