docs: address /judge-readme findings across all READMEs, add MIT LICENSE

- Add standard MIT LICENSE (referenced by every README but previously missing)
- Root README: link License section to ./LICENSE
- adapters/README: fix stale src/index.ts line refs, correct test spec
  path and count (38 -> 31), restore LICENSE link
- adapters/cf/README: rewrite test-parity claim to match actual spec
  coverage, drop misplaced PR-opportunity pitch
- adapters/pg/README: add badges, status callout, TOC, peer-dep ranges,
  Contributing/Changelog sections, fix inverted Quick Start layering
  and your-repo placeholder

Author: techiejd

LICENSE

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2025 techiejd
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

README.md

@@ -1026,4 +1026,4 @@ See [CHANGELOG.md](./CHANGELOG.md) for release history, migration notes, and upg
 
 ## License
 
-MIT
+[MIT](./LICENSE)