Phase 6a-6d: Consolidate and clean up

6a: Delete dead standalone tollgate_core/ (12 files, never compiled)
6b: Rewrite dns_server.c as thin shim to component's tollgate_core_dns
    - Fix component DNS to bind to AP IP instead of INADDR_ANY
6c: Rewrite stratum_proxy.c as thin shim with struct cast to component types
6d: Move sandbox logic into component's tollgate_core_firewall
    - Add tollgate_core_fw_set_sandbox_ports/set_sandbox_mint_access
    - Add is_sandbox_allowed() to component's ip4_canforward_filter
    - Clean main/firewall.c to delegate filter to component
    - Remove redundant DNS auth double-calls from main firewall
Add ROADMAP.md with full extraction plan and checklists

All 21 unit tests pass. ESP-IDF build passes.

1 files changed, 0 insertions, 42 deletions

diff --git a/tollgate_core/src/tollgate_session.h b/tollgate_core/src/tollgate_session.h
deleted file mode 100644
index 4008b24..0000000
--- a/tollgate_core/src/tollgate_session.h
+++ /dev/null
@@ -1,42 +0,0 @@
-#ifndef TOLLGATE_CORE_SESSION_H
-#define TOLLGATE_CORE_SESSION_H
-
-#include <stdint.h>
-#include <stdbool.h>
-
-#define TG_SESSION_MAX_CLIENTS     10
-#define TG_SESSION_MAX_MAC_LEN     18
-
-typedef enum {
-    TG_PAYMENT_CASHU,
-    TG_PAYMENT_MINING,
-    TG_PAYMENT_BYTES
-} tg_payment_method_t;
-
-typedef struct {
-    uint32_t client_ip;
-    char mac[TG_SESSION_MAX_MAC_LEN];
-    uint64_t allotment_ms;
-    int64_t start_time_ms;
-    uint64_t allotment_bytes;
-    uint64_t bytes_consumed;
-    tg_payment_method_t payment_method;
-    bool active;
-} tg_session_t;
-
-int tg_session_init(void);
-tg_session_t *tg_session_create(uint32_t client_ip, uint64_t allotment_ms);
-tg_session_t *tg_session_create_bytes(uint32_t client_ip, uint64_t allotment_bytes);
-void tg_session_add_bytes(uint32_t client_ip, uint64_t bytes);
-tg_session_t *tg_session_find_by_ip(uint32_t client_ip);
-tg_session_t *tg_session_find_by_mac(const char *mac);
-void tg_session_extend(tg_session_t *session, uint64_t additional_ms);
-bool tg_session_is_expired(const tg_session_t *session);
-void tg_session_revoke(tg_session_t *session);
-void tg_session_revoke_all(void);
-int tg_session_active_count(void);
-void tg_session_tick(void);
-tg_session_t *tg_session_get_array(void);
-int tg_session_get_array_size(void);
-
-#endif