feat(api): enhance image module management and export functionality

- Added read-write access to the darktable SQLite catalog for module parameter edits.
- Implemented new endpoints for exporting images and retrieving full-resolution images.
- Introduced PATCH method for updating module parameters with optional preview.
- Added comprehensive tests for new API functionalities, including module retrieval and error handling.
- Updated CORS headers to support new HTTP methods.
- Created detailed documentation for new API endpoints and module operations.

contrib/darktable-api/server.lua

@@ -38,8 +38,13 @@ router.get("/health",                    api.health)
 
 router.get("/api/v1/images",             api.list_images)
 router.get("/api/v1/images/:id",         api.get_image)
-router.get("/api/v1/images/:id/preview", api.get_preview)
-router.post("/api/v1/images/:id/refresh", api.refresh_cache)
+router.get("/api/v1/images/:id/preview",         api.get_preview)
+router.get("/api/v1/images/:id/full",            api.get_full)
+router.post("/api/v1/images/:id/refresh",        api.refresh_cache)
+router.post("/api/v1/images/:id/export",         api.trigger_export)
+router.get("/api/v1/images/:id/modules",         api.list_modules)
+router.get("/api/v1/images/:id/modules/:op",     api.get_module)
+router.patch("/api/v1/images/:id/modules/:op",   api.patch_module)
 
 router.get("/api/v1/tags",               api.list_tags)
 router.get("/api/v1/films",              api.list_films)
@@ -47,11 +52,11 @@ router.get("/api/v1/films",              api.list_films)
 -- ── HTTP helpers ──────────────────────────────────────────────────────────────
 
 local STATUS_TEXT = {
-  [200] = "OK",           [201] = "Created",      [204] = "No Content",
+  [200] = "OK",           [201] = "Created",   [202] = "Accepted",  [204] = "No Content",
   [301] = "Moved Permanently",
   [400] = "Bad Request",  [401] = "Unauthorized", [403] = "Forbidden",
   [404] = "Not Found",    [405] = "Method Not Allowed",
-  [500] = "Internal Server Error",
+  [500] = "Internal Server Error", [504] = "Gateway Timeout",
 }
 
 local function url_decode(s)
@@ -110,7 +115,7 @@ end
 
 local CORS_HEADERS = {
   ["Access-Control-Allow-Origin"]  = "*",
-  ["Access-Control-Allow-Methods"] = "GET, POST, OPTIONS",
+  ["Access-Control-Allow-Methods"] = "GET, POST, PATCH, PUT, DELETE, OPTIONS",
   ["Access-Control-Allow-Headers"] = "Authorization, Content-Type",
   ["Access-Control-Max-Age"]       = "86400",
 }