slurmrestd - Move http_context_t typedef

Change http_context_t into opaque type while only being defined in http.c.

Issue: 50189
diff --git a/src/slurmrestd/http.c b/src/slurmrestd/http.c
index a3804c7..929db25 100644
--- a/src/slurmrestd/http.c
+++ b/src/slurmrestd/http.c
@@ -95,6 +95,22 @@
 	} http_version;
 } request_t;
 
+typedef struct http_context_s {
+	int magic; /* MAGIC */
+	/* reference to assigned connection */
+	conmgr_fd_ref_t *ref;
+	/* assigned connection */
+	conmgr_fd_t *con;
+	/* Authentication context (auth_context_type_t) */
+	void *auth;
+	/* callback to call on each HTTP request */
+	on_http_request_t on_http_request;
+	/* http parser plugin state */
+	http_parser_state_t *parser;
+	/* http request_t */
+	void *request;
+} http_context_t;
+
 /* default keep_alive value which appears to be implementation specific */
 static int DEFAULT_KEEP_ALIVE = 5; //default to 5s to match apache2
 
diff --git a/src/slurmrestd/http.h b/src/slurmrestd/http.h
index c99da56..bf10c8d 100644
--- a/src/slurmrestd/http.h
+++ b/src/slurmrestd/http.h
@@ -58,21 +58,8 @@
  */
 typedef int (*on_http_request_t)(on_http_request_args_t *args);
 
-typedef struct {
-	int magic;
-	/* reference to assigned connection */
-	conmgr_fd_ref_t *ref;
-	/* assigned connection */
-	conmgr_fd_t *con;
-	/* Authentication context (auth_context_type_t) */
-	void *auth;
-	/* callback to call on each HTTP request */
-	on_http_request_t on_http_request;
-	/* http parser plugin state */
-	http_parser_state_t *parser;
-	/* http request_t */
-	void *request;
-} http_context_t;
+/* Opaque connection context */
+typedef struct http_context_s http_context_t;
 
 typedef struct on_http_request_args_s {
 	const http_request_method_t method; /* HTTP request method */