feat: reach the rest of Gitea with kettle api, and drop tea

The plugin required `tea`, Gitea's own CLI, for everything that is not an
issue: releases, pull requests, milestones, branches, actions, webhooks. That
put a second binary, a second set of logins nothing here could see, and 400
lines documenting somebody else's flags outside anything this repository can
test. One command over the transport that already existed removes all three.

Transport: `post` — the hand-rolled request the SDK cannot express, written for
the dependency endpoint — is generalized to an exported `Do`, and `post` is
three lines on top of it. Same http.Client, so the same RoundTripper files the
body under .kettle/payload/, the same `token …` header authenticates it, and a
non-2xx is the same *APIError. It does not paginate, does not reformat the
answer, and names no domain concept, so the layering test is untouched.

The endpoint rule is `tea api`'s, so an endpoint table written for that tool
still works — with one restriction it did not have: a full URL must be on this
instance. Every request carries the project's token in a header, and a URL on
another host would hand the token to whatever was typed.

Command: `kettle api <endpoint>` in a new `api` group, so the generator writes
plugins/kettle/skills/api/SKILL.md — group, directory and /kettle:api are one
word. No --repo and no --login, for the reason no sync command has them: a
cross-repository address is an address, and another instance is KETTLE_URL.
`-X DELETE` needs `--yes`; a flag typed on purpose is an operator's decision.

Scopes: a token minted for issues carries write:issue and answers 403 on the
first request outside issues, naming no scope. Gitea cannot be asked what a
token may do — its own token listing needs a password — so `auth add --scopes`
records it, `auth list` and `config` show it, and a 403 says which category it
is likely to be. Documentation only; nothing is checked against it.

skills/use — the tea reference, 239 lines of it — becomes skills/api: what to
ask for, which endpoints paginate, and how to write a body. Every mention of
`tea` as a requirement is gone from the manifests, the READMEs, the runner and
the four other skills; what survives is the back-compat with the old plugin,
which is a decision and not a debt.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

cli/internal/cmd/AGENTS.md

@@ -39,8 +39,8 @@ anything — which is how the doc generator reads them.
 
 **The tree is flat.** `kettle new`, not `kettle issue new`: an agent pays for every
 token of every invocation, and the grouping that matters for reading is carried in
-`Group` and only shows up in the docs. Three groups, in presentation order:
-`project`, `issue`, `sync`.
+`Group` and only shows up in the docs. Four groups, in presentation order:
+`project`, `issue`, `sync`, `api`.
 
 | file | what is in it |
 |---|---|
@@ -51,10 +51,16 @@ token of every invocation, and the grouping that matters for reading is carried
 | `init.go` `auth.go` `config.go` `version.go` | group `project`. `version.go` also holds `Version`, the string a release build stamps in with `-ldflags -X` |
 | `new.go` `check.go` `ac.go` `tree.go` `index.go` `evict.go` | group `issue` — no network in any of them |
 | `pull.go` `push.go` `remote.go` `comment.go` `close.go` `labels.go` `evict_sync.go` | group `sync` |
+| `api.go` | group `api`, alone in it: one request to an endpoint nothing here wraps |
 | `cli_test.go` | builds the binary in `TestMain`, runs it as a subprocess |
-| `sync_pull_test.go` `sync_write_test.go` | the tracker halves, against fake servers |
+| `sync_pull_test.go` `sync_write_test.go` `api_test.go` | the tracker halves, against fake servers |
 | `gen_test.go` | the generator: determinism, the region splice, the missing-marker refusal |
 
+The fourth group is one command and was still worth naming, because a group is a
+skill directory over in the plugin: `api` is a subject somebody loads on its own —
+which endpoint, and does it paginate — and folding it into `sync` would have put
+"how do I cut a release" behind a skill about the issue round trip.
+
 ## Three conventions every command follows
 
 **Flags may come after positionals.** The standard `flag` package stops parsing at
@@ -84,6 +90,20 @@ login a project runs under is a fact about the project, stated once by
 `kettle init`. That the two could disagree is what the Python version needed a
 `PreToolUse` hook to police.
 
+`api` keeps that rule and needs no flag to: a cross-repository address is an
+address, so `repos/other-owner/other-repo/releases` is simply a path with nothing
+to substitute — `{owner}` and `{repo}` are filled in only where they are spelled.
+Another **instance** is `KETTLE_URL`/`KETTLE_TOKEN`, and a full URL pointing at a
+host that is not this project's is refused by the transport rather than sent with
+the token attached. It also resolves the store it never reads, exactly as `labels`
+does, so "there is no project here" fails the same way for every command that
+talks to a tracker.
+
+**`-X DELETE` needs `--yes`.** The only gate of its kind in the tree, and it is
+here because this is the only command that can delete something that is not an
+issue — a release, a tag, a branch — from an argument. A flag typed on purpose is
+an operator's decision; everything else about the request goes out as spelled.
+
 `--out` is the one flag almost every command has, and an explicit one is used
 **exactly as typed**: a relative `--out` stays relative to the working directory,
 because that is what the operator asked for.
@@ -169,7 +189,10 @@ useful: it writes nothing and exits 1 when anything on disk differs, which is wh
 pre-commit hook or a CI step calls, and it wins over `--dry-run`.
 
 One file per **group**, so adding a group here adds a skill directory over there;
-name one only when it is a subject somebody would load on its own. A command with no
+name one only when it is a subject somebody would load on its own. `api` was
+added exactly that way, and the first `gen skills` run after it wrote a stub whose
+`description:` said TODO — a stub is not shippable, and filling that line in by
+hand is the last step of adding a group, not an optional one. A command with no
 `Group` is in no skill and the run says so. A `Long` or `Example` that spells a
 region marker out in full is a hard error — the generated block would end inside
 itself.
@@ -180,8 +203,8 @@ itself.
   three conventions, the round trip, the generator. The file table names every
   source file in this directory.
 - **Update it when** a command file is added or removed, a group is added, a shared
-  helper in `flags.go`/`sync.go` changes, an exit code gains a meaning, or the
-  push/pull ordering guarantees change.
+  helper in `flags.go`/`sync.go` changes, an exit code gains a meaning, a command
+  gains a confirmation gate, or the push/pull ordering guarantees change.
 - **Do not** copy a flag list or a command's `Long` text here. `kettle help <name>`
   and the generated SKILL.md blocks are the two places that exist for it, and a
   third would be the one that drifts.