ip tagging: refactor ip tagging to make it lock free

[wbpcode]

Commit Message: ip tagging: refactor ip tagging to make it lock free
Additional Description:

Make the ip tagging lock free and removed unnecessary update callback of data source.

Risk Level: mid.
Testing: unit.
Docs Changes: n/a.
Release Notes: n/a.
Platform Specific Features: n/a.

[wbpcode]

/gemini review

[gemini-code-assist]

Code Review

This pull request refactors the IP tagging filter to use atomic snapshots for tries and statistics, ensuring that lookups and stat increments remain consistent during file reloads. It also simplifies the general DataSourceProvider by removing the data_update_cb mechanism. A high-severity issue was identified where validation_visitor is captured by reference in a lambda within a singleton-managed provider, potentially leading to use-after-free bugs if the provider outlives the configuration.

[Copilot]

Pull request overview

Refactors the HTTP IP tagging filter to publish immutable “loaded snapshot” objects (trie + matching stats container) so request-path lookups and stat updates can be performed without locking, and removes the unused/incorrect DataSourceProvider update callback mechanism.

Changes:

• Introduce LoadedIpTags snapshots and IpTagsStats to keep trie + per-tag builtin stat names consistent across reloads.
• Rework IpTagsProvider to publish LoadedIpTags atomically from the datasource transform callback (enabling lock-free request path).
• Remove DataUpdateCb support from Config::DataSource::DataSourceProvider / DynamicData.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 1 comment.

File	Description
test/extensions/filters/http/ip_tagging/ip_tagging_filter_test.cc	Updates tests to validate sharing behavior via the new LoadedIpTags snapshot/trie access.
source/extensions/filters/http/ip_tagging/ip_tagging_filter.h	Introduces IpTagsStats + LoadedIpTags and updates provider/config APIs to use snapshots.
source/extensions/filters/http/ip_tagging/ip_tagging_filter.cc	Implements snapshot creation on load/reload and updates filter request path to use a single per-request snapshot.
source/common/config/datasource.h	Removes DataUpdateCb plumbing from DynamicData/DataSourceProvider and associated invocation logic.

[wbpcode]

/retest