Add BSA in-memory extraction and nested preview support

bsatk:
- Archive::extractToMemory() extracts a file directly into a byte buffer
  instead of a filesystem path, backed by a std::ostringstream sink.
- Archive::findFile() locates a file by relative path, case-insensitive
  and separator-agnostic, walking the folder tree recursively.
- extractDirect/extractCompressed now take std::ostream& so both the
  ofstream and ostringstream paths share the same implementation.

libbsarch: shim rewrite on Linux to map the Windows API surface onto
bsatk::Archive, enabling preview_bsa to open vanilla BSAs via the
same interface as other plugins.

preview_bsa: double-click on a file in the BSA tree now extracts the
bytes via extractToMemory() and hands them to IOrganizer::previewFileData
for nested preview rendering (e.g. NIF inside a BSA).

uibase + organizerproxy + organizercore: new IOrganizer::previewFileData
virtual that routes in-memory file bytes through the first registered
IPluginPreview matching the extension. Uses heap + WA_DeleteOnClose +
open() to avoid nested exec() softlock from mod info filetree ->
preview_bsa tree -> nif preview.

docker/build-inner.sh: stage preview_nif shaders into plugin_data/shaders
so ShaderManager can load them via IOrganizer::getPluginDataPath().

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

1 files changed, 10 insertions, 0 deletions

diff --git a/docker/build-inner.sh b/docker/build-inner.sh
index 0b1d86b..64efa13 100755
--- a/docker/build-inner.sh
+++ b/docker/build-inner.sh
@@ -109,6 +109,16 @@ if [ -d "libs/preview_dds/src/DDS" ]; then
 fi
 [ -d "build/src/src/plugins/data" ] && cp -a "build/src/src/plugins/data" "${OUT_DIR}/plugins/"
 
+# preview_nif shaders. ShaderManager loads them from
+# IOrganizer::getPluginDataPath()/shaders/, which on Linux is
+# OrganizerCore::pluginDataPath() = <basePath>/plugin_data (see
+# src/src/organizercore.cpp:971). Stage accordingly.
+if [ -d "libs/preview_nif/data/shaders" ]; then
+    mkdir -p "${OUT_DIR}/plugin_data/shaders"
+    find "libs/preview_nif/data/shaders" -type f \( -name "*.vert" -o -name "*.frag" \) \
+        -exec cp -f {} "${OUT_DIR}/plugin_data/shaders/" \;
+fi
+
 # ── Stylesheets (themes) ──
 if [ -d "build/src/src/stylesheets" ]; then
     cp -a "build/src/src/stylesheets" "${OUT_DIR}/"