libpanto API fixes

- FSJSONLStore: don't require `cwd`, instead panto CLI provides it in
  the session metadata
- Lua: expose the `SessionStore` interface and the `FSJSONLStore` and
  `NullStore` implementations
- C: use idiomatic `const char *` for incoming strings
- C: expose the `FSJSONLStore` and `NullStore` implementations

1 files changed, 9 insertions, 7 deletions

diff --git a/libpanto-c/include/panto.h b/libpanto-c/include/panto.h
index 4430810..4f69465 100644
--- a/libpanto-c/include/panto.h
+++ b/libpanto-c/include/panto.h
@@ -39,10 +39,10 @@ typedef struct { PantoAPIStyle api_style; PantoSlice base_url; PantoSlice model;
 typedef struct { PantoSlice id, created, modified, last_user_message, base_url, model; size_t message_count; PantoAPIStyle api_style; PantoReasoningEffort reasoning; } PantoSessionInfo;
 typedef struct { PantoSessionInfo *ptr; size_t len; } PantoSessionInfoList;
 typedef struct { bool found; PantoSession *session; } PantoSessionResult;
-typedef struct { PantoSlice api_key, base_url, model; PantoReasoningEffort reasoning; uint32_t max_tokens; } PantoOpenAIChatConfig;
-typedef struct { PantoSlice api_key, base_url, model, api_version; uint32_t max_tokens; PantoThinking thinking; PantoEffort effort; bool has_thinking_budget_tokens; uint32_t thinking_budget_tokens; bool thinking_interleaved; } PantoAnthropicMessagesConfig;
+typedef struct { const char *api_key, *base_url, *model; PantoReasoningEffort reasoning; uint32_t max_tokens; } PantoOpenAIChatConfig;
+typedef struct { const char *api_key, *base_url, *model, *api_version; uint32_t max_tokens; PantoThinking thinking; PantoEffort effort; bool has_thinking_budget_tokens; uint32_t thinking_budget_tokens; bool thinking_interleaved; } PantoAnthropicMessagesConfig;
 typedef struct { PantoAPIStyle tag; union { PantoOpenAIChatConfig openai_chat; PantoAnthropicMessagesConfig anthropic_messages; } data; } PantoProviderConfig;
-typedef struct { uint32_t keep_verbatim; bool has_model; PantoProviderConfig model; bool has_compaction_prompt; PantoSlice compaction_prompt; } PantoCompactionConfig;
+typedef struct { uint32_t keep_verbatim; bool has_model; PantoProviderConfig model; bool has_compaction_prompt; const char *compaction_prompt; } PantoCompactionConfig;
 typedef struct { size_t max_attempts; uint64_t initial_delay_ms, max_delay_ms; double multiplier; bool jitter; } PantoRetryConfig;
 typedef struct { PantoProviderConfig provider; PantoCompactionConfig compaction; PantoRetryConfig retry; } PantoConfig;
 
@@ -81,19 +81,21 @@ PANTO_EXPORT PantoStatus panto_session_create(PantoSessionStore *store, PantoSes
 PANTO_EXPORT void panto_session_destroy(PantoSession *session);
 PANTO_EXPORT PantoStatus panto_session_store_create(void *ctx, const PantoSessionStoreVTable *vtable, PantoSessionStore **out);
 PANTO_EXPORT void panto_session_store_destroy(PantoSessionStore *store);
+PANTO_EXPORT PantoStatus panto_null_store_create(PantoSessionStore **out);
+PANTO_EXPORT PantoStatus panto_file_system_jsonl_store_create(const char *dir, const char *metadata, PantoSessionStore **out);
 PANTO_EXPORT PantoStatus panto_session_store_create_session(PantoSessionStore *store, PantoSession **out);
 PANTO_EXPORT PantoStatus panto_session_store_list(PantoSessionStore *store, PantoSessionInfoList *out);
 PANTO_EXPORT void panto_session_info_list_destroy(PantoSessionInfoList infos);
-PANTO_EXPORT PantoStatus panto_session_store_resolve(PantoSessionStore *store, PantoSlice id, PantoSessionResult *out);
+PANTO_EXPORT PantoStatus panto_session_store_resolve(PantoSessionStore *store, const char *id, PantoSessionResult *out);
 PANTO_EXPORT PantoStatus panto_session_store_latest(PantoSessionStore *store, PantoSessionResult *out);
 PANTO_EXPORT PantoStatus panto_session_load(PantoSession *session, PantoConversation **out);
 PANTO_EXPORT PantoStatus panto_agent_create(const PantoConfig *config, PantoSession *session, PantoConversation *conversation, PantoAgent **out);
 PANTO_EXPORT void panto_agent_destroy(PantoAgent *agent);
 PANTO_EXPORT PantoSlice panto_agent_session_id(PantoAgent *agent);
 PANTO_EXPORT PantoStatus panto_agent_set_config(PantoAgent *agent, const PantoConfig *config);
-PANTO_EXPORT PantoStatus panto_agent_add_system_message(PantoAgent *agent, PantoSlice text);
-PANTO_EXPORT PantoStatus panto_agent_set_system_prompt(PantoAgent *agent, PantoSlice text);
-PANTO_EXPORT PantoStatus panto_agent_run(PantoAgent *agent, PantoSlice user_text, PantoStream **out);
+PANTO_EXPORT PantoStatus panto_agent_add_system_message(PantoAgent *agent, const char *text);
+PANTO_EXPORT PantoStatus panto_agent_set_system_prompt(PantoAgent *agent, const char *text);
+PANTO_EXPORT PantoStatus panto_agent_run(PantoAgent *agent, const char *user_text, PantoStream **out);
 PANTO_EXPORT void panto_stream_destroy(PantoStream *stream);
 PANTO_EXPORT PantoNextStatus panto_stream_next(PantoStream *stream, PantoEvent *out);
 PANTO_EXPORT void panto_event_free(PantoEvent *event);