Update the implementation of the `toString` fhirpath function to: (pending FHIR-48737)
* not return the text 'null' when no primitive value exists (when extension only)
* throw an error if more than 1 item is to be returned (doesn't support collections)
* return an empty set when no primitive values exist (when extension only)
## Validator Changes
* Improve warning messages about collections in SQL ViewDefinitions
* Fix type evaluation of .item() in FHIRPath
* Revise message about unknown usage context on additional binding
* Add support for code generation
* Add check for # in CanonicalResource.version
* Fix problem parsing urls in cds-hooks formats
* Fix issues with output folder running tx tests
* Fix bug evaluating resolve() in contained resources when doing slicing
## Other code changes
* Fix NPE processing markdown
* Capture missing snapshot generation messages
* Track OID status
* Improve rendering of coded values
* update tests for changes to PE code generation
* Tx Tests: Add support for special header on specific tests
* Tx Tests: Fix framework to handle diagnostics correctly
* Tx Tests: check http code in tx test cases
* Add support for NCI code rendering
* Adding missing lombok annotation (cannot build without it from scratch) (#1785)
* Remove Encounter Renderer
* Profile code generation fixes
* Add r4 code gen classes
* Draft work for tx server authentication (not landed yet)
* Move XXE safe SAXParserFactory and XMLReader instantiation to XMLUtil
* Bump commons-compress version
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## Validator Changes
* Fix validation issue with open-choice questions in R4 questionnaires
* Add command line parameter ```-tx-routing```
* Add command line parameter ```-clear-tx-cache```
* Add command line parameter ```-advisor-file```
## Other code changes
* Render extensions on some data types
* Fix rendering of complex data types when doing profile rendering
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## Validator Changes
* Don't send expansion to tx server if there's a compose when sending value sets
* Better handling of error messages from terminology servers
* Stop hitting VSAC server directly
## Other code changes
* Add support for $id$ in terminology tests
* Move new documentbuilderfactory calls to XMLUtils (Security)
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## Validator Changes
* Show message ids in validator (-show-message--ids)
* Fix bug where message id not showing for slicing messages
* Add advisor documentation (not yet functional)
* Fix issue checking package currency for #current packages
* Add warning when code system is marked complete but has no content
* Fix bug processing adding discriminators in derived profiles
* Break valueset concept validation into multiple smaller batches for performance reasons
## Other code changes
* More work on translations in IGs
* Override inheritance of HAPI's old maven-compiler-plugin
* do not use loadPackageFromCacheOnly from outside cache manager
* Fix issues with rendering example scenario
* refactor sql view validation to fix NPE
* Fix misc warnings flagged by builds (#1772) + TRIVY typo
* Bump codeql actions to v3
* Bump checkout action to v4
* Bump commons.io to 2.14.0 (#1771)
* Workaround for ghcr rate limiting of trivy db downloads (#1770)
* Add VSACfinder (template for package analysis)
* Fix github urls
* Spelling fixes
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Brian Postlethwaite
dotasek
markiantorno
Grahame Grieve
Grahame Grieve
dotasek