nautd/webui: scripting, labels, settings, set-location, pause fix

Session checkpoint on webui-plugin:
- engine dump (nautctl dump) + engine endgame integration
- per-file move locations persistence; torrent-level "Set location"
  with reset/keep-relative/leave-separate handling + residual prune
- Lua: naut.get_labels, define_settings/get_setting (script_host struct)
- daemon-owned labels (category+tags) + taxonomy persistence; webui write-through
- fix: pausing a completed/seeding torrent now sticks (stop wins over result)
- automation tab responsive layout; anime_sort label gating + settings

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

include/naut/tracker.h

@@ -1,9 +1,9 @@
-/* tracker.h — HTTP and UDP tracker clients (BEP-3/BEP-23, BEP-15).
+/* tracker.h — HTTP and UDP tracker announce client.
  *
- * Split into pure codec (URL building, bencode response parsing, UDP packet
- * encode/decode — all unit-testable without a socket) and thin blocking fetch
- * helpers used by the swarm app. HTTPS/TLS is deferred to a later transport
- * backend; the built-ins in this phase are plaintext HTTP and UDP.
+ * The wire codec (query building, bencode/UDP packet encode+decode) lives in the
+ * sibling `torrent-tracker` library; the implementation here (src/discovery)
+ * owns only the socket glue. HTTPS/TLS is deferred to a later transport backend;
+ * the built-ins are plaintext HTTP and UDP.
  */
 #ifndef NAUT_TRACKER_H
 #define NAUT_TRACKER_H
@@ -37,25 +37,10 @@ typedef struct {
 
 void naut_tracker_response_free(naut_tracker_response *r);
 
-/* --- HTTP --- */
 /* Build the full announce GET URL (base?...params) with percent-encoded binary
  * info_hash/peer_id. Returns bytes written (excl NUL) or 0 on overflow. */
 size_t naut_tracker_http_url(const char *base, const naut_announce_req *req,
                              char *out, size_t outsz);
-/* Parse a bencoded HTTP tracker response body (compact or dict peer list). */
-naut_err naut_tracker_parse_http(const uint8_t *body, size_t len,
-                                 naut_tracker_response *out);
-
-/* --- UDP (BEP-15): pure packet codec --- */
-#define NAUT_UDP_CONNECT_REQ_LEN   16
-#define NAUT_UDP_ANNOUNCE_REQ_LEN  98
-void     naut_udp_build_connect(uint8_t out[16], uint32_t txid);
-naut_err naut_udp_parse_connect(const uint8_t *in, size_t len, uint32_t txid,
-                                uint64_t *connection_id);
-void     naut_udp_build_announce(uint8_t out[98], uint64_t connection_id,
-                                 uint32_t txid, const naut_announce_req *req);
-naut_err naut_udp_parse_announce(const uint8_t *in, size_t len, uint32_t txid,
-                                 naut_tracker_response *out);
 
 /* --- live fetch helpers (blocking) --- */
 /* HTTP GET the announce URL; fills out. Only http:// (no TLS yet). */