Last obs before exposure flag and baseline flag (#49)

* WIP: Baseline flag code adaptation, not functional yet

* WIP: working code, pending tests for baseline logic due to lack of examples

* remove files as added in examples

* modified function

* Harmonize input parameters with other derive_studyday function

* Switched from checkmate to admiraldev assertions; added tests for example + validations

* styler

* lintr fixes

* Fixed baseline visit feature and added a test case

* Run Styler

* Fix pipeline failures

* Fix pipeline failure

* Fix style

* Fix pipeline failure

* fix pipeline failures

* Fix pipeline failures

* Fix styler issues

* Review comments

* Fix errors

* fix spelling

---------

Co-authored-by: Rammprasad Ganapathy <ganapathy.rammprasad@gene.com>
Co-authored-by: Edgar Manukyan <edgar.manukyan@roche.com>

.lintr

@@ -23,6 +23,8 @@ linters: linters_with_defaults(
     redundant_ifelse_linter(),
     sprintf_linter(),
     strings_as_factors_linter(),
-    undesirable_function_linter(c(Sys.setenv = NA_character_, mapply = NA_character_))
+    undesirable_function_linter(c(Sys.setenv = NA_character_, mapply = NA_character_)),
+    object_name_linter = NULL,
+    object_usage_linter = NULL
   )
 encoding: "UTF-8"

NAMESPACE

@@ -13,9 +13,11 @@ export(create_iso8601)
 export(ct_map)
 export(ct_spec_example)
 export(ct_spec_vars)
+export(derive_blfl)
 export(derive_seq)
 export(derive_study_day)
 export(domain_example)
+export(dtc_timepart)
 export(fmt_cmp)
 export(generate_oak_id_vars)
 export(hardcode_ct)