feat: add the kettle CLI, replacing the plugin's Python scripts

The plugin resolved its issue store from `__file__`, which put it inside a
versioned plugin cache: issues written from one project were invisible from the
next, and `origin: local` files — the only copy of that work by definition —
were stranded a version bump at a time. The walk that answers "which directory
is the project" was written three times over, and in a linked worktree the three
disagreed. Both are runtime failures rather than logic ones, so the fix is a
compiled binary: one walk, imported rather than re-derived, and a layering rule
the build graph enforces instead of a grep.

Seven packages, knowledge flowing one way. `project` answers which directory is
the project and depends on nothing. `issue` is the domain — format, taxonomy,
validation, checkboxes, dependency graph, the store, eviction — offline, with no
tracker in it. `wire` holds the protocol shapes. `gitea` is the transport,
`mapping` the bridge, `config` the credentials, `cmd` the command tree. Four
tests hold the boundaries, each failing on a real mistake rather than a naming
convention.

The marker moves to `.kettle/` and the login pin moves out of the harness's
settings file into `.kettle/config.yaml`, which pins a login by NAME; the tokens
live in one file per machine, mode 0600, outside every working tree. That
retires the PreToolUse guard hook entirely — the binary holds its own
credentials, so a command running under a login nobody chose is not expressible
rather than caught.

`kettle init` migrates an older `tmp/issues` or `.tea/issues` store in, as a
move: a store left behind at an old path is one somebody edits by accident
months later.

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

cli/internal/cmd/index.go

@@ -0,0 +1,46 @@
+package cmd
+
+import (
+	"flag"
+	"fmt"
+
+	"git.noodles.cam/claude-skills/marketplace/cli/internal/issue"
+)
+
+func init() {
+	register(&Command{
+		Name:  "index",
+		Group: GroupIssue,
+		Short: "rebuild INDEX.md from what is on disk",
+		Long: `A map of the local store, nothing else. The ` + "`origin`" + ` column is the only place
+the index acknowledges that a tracker exists: ` + "`local`" + ` means the issue has never
+left this machine, anything else names the tracker it also lives in. Both are
+ordinary issues here.
+
+` + "`progress`" + ` counts the body's checkboxes, ticked over total, and is read off the
+body at build time rather than stored — a second copy of that state in a
+metadata field would be wrong by the next edit.
+
+An existing store with nothing in it is a legitimate thing to index and gets an
+"_empty_" table. A store that is not there is an error, not a directory to
+create.`,
+		Examples: []Example{
+			{"kettle index", "rebuild the index for this project"},
+		},
+		Setup: func(fs *flag.FlagSet) func([]string) error {
+			out := storeFlag(fs)
+			return func(args []string) error {
+				root, err := storeRoot(*out)
+				if err != nil {
+					return err
+				}
+				path, n, err := issue.BuildIndex(root)
+				if err != nil {
+					return Fail("%v — nothing was created; create an issue with `kettle new`, or pass --out", err)
+				}
+				fmt.Printf("%s — %d issue(s)\n", path, n)
+				return nil
+			}
+		},
+	})
+}