Refactor: eliminate export script service-layer duplication (~700 LOC) closes #42 (#61)

* initial implementation of export refinements

* refactor: eliminate remaining duplications from export pipeline

Extract _load_bubble_map/_load_project_layouts_map/_load_code_block_diff_map
to services/workspace_db.py; add cursor_ide_chat_to_markdown to
utils/cursor_md_exporter.py; remove private _slug() copies from
api/export_api.py and utils/cursor_md_exporter.py.

* fix: inconsistent YAML escaping for workspace_name

* fix: review comments

* fix: state_path omits an encoding

Author: bradjin8

api/export_api.py

@@ -16,7 +16,7 @@
 from utils.workspace_path import resolve_workspace_path, get_cli_chats_path
 from utils.cli_chat_reader import list_cli_projects
 from utils.path_helpers import get_workspace_folder_paths, get_workspace_display_name
-from utils.workspace_descriptor import _read_json_file
+from utils.workspace_descriptor import read_json_file
 from services.workspace_resolver import (
     _infer_workspace_name_from_context,
     # Re-exported for back-compat with existing tests that import from api.workspaces
@@ -107,7 +107,7 @@ def get_workspace(workspace_id):
         folder = None
         workspace_name = workspace_id
         try:
-            wd = _read_json_file(wj_path)
+            wd = read_json_file(wj_path)
             folder_paths = get_workspace_folder_paths(wd)
             folder = folder_paths[0] if folder_paths else wd.get("folder")
             derived_name = get_workspace_display_name(wd)