feat: Adopt W3C JWE standard for encryption

[macterra]

Replace custom ECIES (secp256k1 ECDH + XChaCha20-Poly1305) with standard JWE Compact Serialization (ECDH-ES + A256GCM) per the W3C VC-JOSE-COSE spec. Built using existing @noble primitives to maintain browser compatibility (Web Crypto doesn't support secp256k1).

Backward compatible: legacy ciphertext is auto-detected and decrypted via decryptMessageLegacy/decryptBytesLegacy methods.

[coveralls]

Pull Request Test Coverage Report for Build 22152092432

Details

• 118 of 122 (96.72%) changed or added relevant lines in 4 files are covered.
• No unchanged relevant lines lost coverage.
• Overall first build on 85-add-JOSE at 95.409%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
packages/cipher/src/jwe.ts	50	51	98.04%
packages/keymaster/src/keymaster.ts	35	36	97.22%
packages/cipher/src/cipher-base.ts	9	11	81.82%

Totals
Change from base Build 22116124280:	95.4%
Covered Lines:	3395
Relevant Lines:	3493

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💛 - Coveralls

[Copilot]

Pull request overview

This pull request replaces the custom ECIES encryption scheme (secp256k1 ECDH + XChaCha20-Poly1305) with standard W3C JWE Compact Serialization (ECDH-ES + A256GCM) to align with the W3C VC-JOSE-COSE specification. The implementation maintains backward compatibility by auto-detecting legacy ciphertext format and providing explicit legacy decryption methods.

Changes:

• Implements JWE Compact Serialization with ECDH-ES key agreement and A256GCM encryption using @noble primitives
• Updates cipher API to use single recipient public key parameter (removing sender private key requirement)
• Migrates message metadata (sender, created) from encrypted payload to DID document controller/metadata fields
• Provides backward compatibility through legacy decryption methods and optional legacyPubKey parameter

Reviewed changes

Copilot reviewed 13 out of 14 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
packages/cipher/src/jwe.ts	New JWE implementation with buildJweCompact/parseJweCompact functions
packages/cipher/src/concat-kdf.ts	Concat KDF implementation per NIST SP 800-56A and RFC 7518
packages/cipher/src/cipher-base.ts	Updated cipher interface with new encryption API and backward compatibility
packages/cipher/src/types.ts	Updated type signatures for encryption methods and added legacy methods
packages/keymaster/src/keymaster.ts	Updated all encryption/decryption call sites to new API, changed message metadata storage
packages/keymaster/src/types.ts	Made EncryptedMessage sender/created fields optional
tests/cipher/jwe.test.ts	Comprehensive tests for JWE implementation and KDF
tests/keymaster/crypto.test.ts	Updated tests to verify new metadata storage approach
services/gatekeeper/client/src/App.js	Updated decryptMessage call with reordered parameters
apps/react-wallet/src/contexts/WalletProvider.tsx	Updated decryptMessage call with reordered parameters
apps/chrome-extension/src/contexts/WalletProvider.tsx	Updated decryptMessage call with reordered parameters
python/keymaster_sdk/tests/test_keymaster_sdk.py	Updated test to check controller field instead of encrypted.sender
jest.config.js	Added module mappings for new JWE and KDF files
package.json	Version bump to 0.3.0 with updated description

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