fix: auto-discover embedded sub-projects (Tauri src-tauri, etc.)

When a directory already has a project signature (e.g. svelte.config.js),
also scan its immediate children for additional project signatures.
This catches hybrid projects like Tauri where the frontend (SvelteKit)
and backend (Rust/Cargo.toml) coexist under the same parent directory.

Generic approach: no framework-specific hardcoding — any sub-directory
with a build file (Cargo.toml, package.json, pom.xml, etc.) inside an
already-detected project is added as a separate project entry.

Before: desktop (sveltekit) — Tauri Rust backend silently ignored
After:  desktop (sveltekit) + src-tauri (tauri, 162 commands, 39 entities)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: Wandererer

codebeacon/discover/detector.py

@@ -228,6 +228,7 @@ def _detect_language_from_files(directory: Path) -> str:
 }
 
 
+
 def _iter_subdirs(directory: Path) -> list[Path]:
     """Return immediate subdirectories, skipping common non-project dirs."""
     try:
@@ -268,13 +269,22 @@ def discover_projects(paths: list[str]) -> list[ProjectInfo]:
     # Level 2: if a subdir has no signature itself, scan its children
     #           (e.g. WaveLog/server, aptscore/frontend, murmur/landing)
     subprojects: list[ProjectInfo] = []
+    seen_paths: set[str] = set()
     for subdir in _iter_subdirs(single_path):
         if _has_project_signature(subdir):
             subprojects.append(_build_project_info(subdir, multi=True))
+            seen_paths.add(str(subdir))
+            # Scan children for embedded sub-projects with their own signature
+            # (e.g. Tauri: desktop/ has svelte.config.js + desktop/src-tauri/ has Cargo.toml)
+            for nested in _iter_subdirs(subdir):
+                if str(nested) not in seen_paths and _has_project_signature(nested):
+                    subprojects.append(_build_project_info(nested, multi=True))
+                    seen_paths.add(str(nested))
         else:
             for nested in _iter_subdirs(subdir):
-                if _has_project_signature(nested):
+                if str(nested) not in seen_paths and _has_project_signature(nested):
                     subprojects.append(_build_project_info(nested, multi=True))
+                    seen_paths.add(str(nested))
 
     if subprojects:
         return subprojects