Add Apache 2.0 license

[usmansalimLM]

Licenses this repo and @likeminds.community/likeminds-feed-reactjs under Apache 2.0.

Changes

File	Change
LICENSE	new — canonical Apache 2.0 text, repo root
NOTICE	new — LikeMinds copyright attribution (required by Apache §4(d))
core/LICENSE	new — same text, so it ships inside the npm tarball
core/package.json	added "license": "Apache-2.0" — there was no license field at all
core/README.md	added a ## License section

The published package declared no license at all

core/package.json had no license field. npm therefore showed
@likeminds.community/likeminds-feed-reactjs with no license, which is the strongest possible
signal to a consumer's compliance tooling that the package cannot be used. This adds it.

npm consumers' scanners read registry metadata, not this repo, so the package.json change
matters as much as the LICENSE file. It takes effect on the next published version only;
1.12.0 and earlier keep "no license" on npm permanently.

Why two LICENSE files

The root LICENSE is what GitHub reads for the repository license badge. But npm packs only
the files inside core/, so the root file would not reach npm consumers. Both are needed and
both are byte-identical. Standard practice for a monorepo that publishes a subdirectory.

The two sample apps are intentionally untouched

social-feed and qna-feed are both marked "private": true and declare no license field.
They are not published and are covered by the root LICENSE.

Notes for the reviewer

The LICENSE files are byte-identical to https://www.apache.org/licenses/LICENSE-2.0.txt
(SHA-256 cfc7749b96f63bd31c3c42b5c471bf756814053e847c10f3eb003417bc523d30). Please do not
reformat them or fill in the Copyright [yyyy] [name of copyright owner] placeholder in the
Appendix — that placeholder is part of the Appendix's instructions, not this repo's copyright
notice. Editing the text makes scanners report "Other" instead of "Apache-2.0". The repo's
copyright notice lives in NOTICE.

Context

@likeminds.community/likeminds-feed-reactjs -> likeminds-feed-reactjs (this repo, public)
└── @likeminds.community/feed-js            -> likeminds-feed-js-data (PRIVATE)

The feed-js dependency is already covered by
LikeMindsCommunity/likeminds-feed-js-data#93, but that repo is still private and must be
opened for this SDK to be usable as open source. That is a separate decision.

Flagged, not changed

This repo has no root README.md. One would normally carry the License section and explain the
monorepo layout. Not added here to avoid inventing project documentation.