Fix session project name mismatch with indexed project name

detect_session used a two-component path algorithm (e.g. "project_dir-
codebase-memory-mcp") while the pipeline used cbm_project_name_from_path
with the full absolute path (e.g. "Users-martinvogel-project_dir-
codebase-memory-mcp"). This caused session queries to look for a .db
file that didn't match the indexed name, silently returning empty results.

Fix: use cbm_project_name_from_path in detect_session so both paths
produce the same project name. Update integration test to accept guard
error after project deletion (correct new behavior from PR #120).

Author: DeusData

src/mcp/mcp.c

@@ -2629,30 +2629,14 @@ static void detect_session(cbm_mcp_server_t *srv) {
         }
     }
 
-    /* Derive project name from path */
+    /* Derive project name from path — must match cbm_project_name_from_path
+     * used by the pipeline, otherwise session queries look for a .db file
+     * that doesn't match the indexed project name. */
     if (srv->session_root[0]) {
-        /* Use last two path components joined by dash, matching Go's ProjectNameFromPath */
-        const char *p = srv->session_root;
-        const char *last_slash = strrchr(p, '/');
-        if (last_slash && last_slash > p) {
-            const char *prev = last_slash - 1;
-            while (prev > p && *prev != '/') {
-                prev--;
-            }
-            if (*prev == '/') {
-                prev++;
-            }
-            snprintf(srv->session_project, sizeof(srv->session_project), "%.*s",
-                     (int)(strlen(p) - (size_t)(prev - p)), prev);
-            /* Replace / with - */
-            for (char *c = srv->session_project; *c; c++) {
-                if (*c == '/') {
-                    *c = '-';
-                }
-            }
-        } else {
-            snprintf(srv->session_project, sizeof(srv->session_project), "%s",
-                     last_slash ? last_slash + 1 : p);
+        char *pname = cbm_project_name_from_path(srv->session_root);
+        if (pname) {
+            snprintf(srv->session_project, sizeof(srv->session_project), "%s", pname);
+            free(pname);
         }
     }
 }

tests/test_integration.c

@@ -406,12 +406,13 @@ TEST(integ_mcp_delete_project) {
     ASSERT_NOT_NULL(strstr(resp, "deleted"));
     free(resp);
 
-    /* After deletion, search should return empty */
+    /* After deletion, search should return an error (not indexed) or empty results */
     snprintf(args, sizeof(args), "{\"label\":\"Function\",\"project\":\"%s\"}", g_project);
     resp = call_tool("search_graph", args);
     ASSERT_NOT_NULL(resp);
-    /* Should show 0 results or empty */
-    ASSERT_NOT_NULL(strstr(resp, "total"));
+    /* Guard returns "not indexed" error or "no project loaded"; either is correct */
+    ASSERT_TRUE(strstr(resp, "total") != NULL || strstr(resp, "not indexed") != NULL ||
+                strstr(resp, "no project loaded") != NULL);
     free(resp);
     PASS();
 }