Propose topic-based notifications for issues and PRs

[jeswr]

Summary

This PR proposes topic-based notifications for the Linked Web Storage specifications, based on the initial assignment sketch.

It adds:

• a structured issue form that asks reporters to select the relevant specification topic; and
• a workflow that mentions the relevant contacts and additional reviewers on matching issues and pull requests.

For issues, the workflow recognizes the topic selected in the form as well as existing topic labels. For pull requests, it infers topics from the changed file paths. A hidden marker ensures each topic is mentioned only once per issue or PR, including after edits or additional commits.

This is notification automation only: it does not add CODEOWNERS, assign issues, require approvals, or require the tagged participants to have repository write access.

Proposed assignments

Topic	Primary contacts	Additional reviewers
Authentication	@jeswr, @acoburn	@ericprud
CRUD operations	@ebremer	—
Metadata and linksets	@ebremer	@termontwouter, @pchampin
Notifications	@laurensdeb	@ericprud
Access requests and grants	@acoburn, @ericprud, @jeswr	—
CI and publication tooling	@pchampin	—
Vocabulary and JSON-LD	@ebremer, @pchampin, @acoburn, @jeswr	—
Test suite	@langsamu, @ebremer, @ericprud	—
Threat model	@renyuneyun, @ericprud	—
Introduction	@jeremycaine, @jeswr, @ebremer	—
Search index	@ebremer, @FabienGandon	—

Consent requested

Please submit an Approve review if you consent to being automatically mentioned for the topics shown above. These checkboxes can be marked as approvals arrive:

• @acoburn
• @ebremer
• @laurensdeb
• @ericprud
• @pchampin
• @langsamu
• @renyuneyun
• @jeremycaine
• @FabienGandon
• @termontwouter
• @jeswr — opening this PR records my consent; GitHub does not allow a PR author to approve their own PR.

Behavior and limitations

• Issues created with the new form are routed from their selected topic. Issues created another way are routed when they carry a recognized existing topic label.
• Pull requests are routed from the files they change and can notify more than one topic group.
• The test-suite mapping reserves /tests/, because this repository does not currently contain a test-suite directory.
• The introduction is embedded in lws10-core/index.html; until it is split into an included file, every direct change to that file is treated as an introduction change.
• The workflow uses pull_request_target so it can comment on pull requests from forks, but it never checks out or executes contributor code. Its permissions are limited to reading repository/PR metadata and writing issue or PR comments.

Verification

• actionlint .github/workflows/notify-topic-participants.yml
• YAML parsing for the issue form and workflow
• JavaScript syntax validation for the embedded github-script
• routing tests for form topics, labels, changed PR paths, metadata/CRUD precedence, and duplicate-comment suppression

[elf-pavlik]

@ericprud looks very busy 🤣