LocID User ID Submodule: add locIdSystem (prebid#14367)

* chore(prebid): scaffold locid user id module

* update LocID module to support first-party endpoint fetching and privacy signal handling

* update LocID system tests for gdpr handling and consent string validation

* Enhance LocID module documentation and tests for privacy signal handling. Updated comments for clarity, added test cases for maximum ID length and empty endpoint handling, and refined privacy configuration notes in the documentation.

* Refactor LocID module to standardize naming conventions and enhance privacy signal handling. Updated module name to 'locId', improved consent data processing functions, and revised documentation and tests accordingly.

* Added Apache 2.0 license header.

* Add LocID User ID sub-module documentation and refactor ajax usage in locIdSystem module

- Introduced locid.md documentation detailing the LocID User ID sub-module, including installation, configuration, parameters, and privacy handling.
- Refactored locIdSystem.js to utilize ajaxBuilder for improved request handling.
- Updated tests in locIdSystem_spec.js to accommodate changes in ajax usage and ensure proper timeout configurations.

* Remove docs folder - to be submitted to prebid.github.io separately

* Update LocID atype to 1 for compliance with OpenRTB 2.6 specifications

- Changed the default EID atype in locIdSystem.js and related documentation from 3384 to 1, reflecting the correct device identifier as per OpenRTB 2.6 Extended Identifiers spec.
- Updated references in locIdSystem.md and userId/eids.md to ensure consistency across documentation.
- Adjusted unit tests in locIdSystem_spec.js to validate the new atype value.

* Enhance LocID module with connection IP handling and response parsing improvements

- Introduced connection IP validation and storage alongside LocID to support IP-aware caching.
- Updated response parsing to only extract `tx_cloc` and `connection_ip`, ignoring `stable_cloc`.
- Enhanced documentation to reflect changes in stored value format and endpoint response requirements.
- Modified unit tests to cover new functionality, including connection IP checks and expiration handling.

* fix getValue string handling, GDPR enforcement gating, extendId docs

* LocID: enforce IP cache TTL in extendId and update tests/docs

* LocID: honor null tx_cloc, reject whitespace-only IDs, add stable_cloc exclusion test

* LocID: remove legacy 3384 references and enforce atype 1

* LocID: add vendorless TCF marker and scope 3384 guard

* enhance locIdSystem to handle whitespace-only tx_cloc and update documentation. Ensure null IDs are cached correctly when tx_cloc is empty or whitespace, and adjust caching logic to honor null responses from the main endpoint.

---------

Co-authored-by: Brian <bcweiss@gmail.com>

Author: 2 people

modules/.submodules.json

@@ -32,6 +32,7 @@
       "kinessoIdSystem",
       "liveIntentIdSystem",
       "lmpIdSystem",
+      "locIdSystem",
       "lockrAIMIdSystem",
       "lotamePanoramaIdSystem",
       "merkleIdSystem",
@@ -147,4 +148,4 @@
       "topLevelPaapi"
     ]
   }
-}
+}