feat(#10548): add TASK, TARGET, USER_SETTINGS constants to DOC_TYPES

[AshayK003]

Summary

Adds DOC_TYPES.TASK, DOC_TYPES.TARGET, and DOC_TYPES.USER_SETTINGS constants to the shared constants library and replaces all magic-string usages in production code.

Changes (6 files, +13/−8):

• shared-libs/constants/src/index.js — Added 3 new constants to DOC_TYPES
• api/src/services/replication/authorization.js — Replaced 'user-settings' and 'task'
• shared-libs/cht-datasource/src/local/target.ts — Added import + replaced 'target'
• shared-libs/rules-engine/src/rules-emitter/emitter.javascript.js — Added import + replaced 'task'/'target'
• webapp/src/ts/modules/tasks/tasks.component.ts — Replaced 'task' (import existed)
• webapp/src/ts/services/rules-engine.service.ts — Replaced 2× 'task' (import existed)

Not changed — CouchDB ddoc files (sandboxed context), form.service.ts (FormType), E2E tests.

Closes #10548

[AshayK003]

Hi maintainers 👋

This PR adds DOC_TYPES.TASK, DOC_TYPES.TARGET, and DOC_TYPES.USER_SETTINGS constants to the shared constants library and replaces all corresponding magic-string usages across the codebase (6 files, +13/−8). Closes #10548.

Could someone please take a look when you get a chance? The CI checks appear to need a maintainer's approval to run from this fork. Happy to address any feedback.

[AshayK003]

@maintainers Bumping for visibility. This adds 3 missing constants (TASK, TARGET, USER_SETTINGS) to the shared DOC_TYPES library and replaces magic strings across 4 files. SonarCloud warnings are all pre-existing in files touched by the diff, not introduced by this change. Happy to address any feedback.