Add the LogicSRC OpenCreds specification (#140)

* Add the LogicSRC OpenCreds specification

Leaving a password manager means writing every secret you own to disk in
the clear, and losing whatever the spreadsheet had no column for. A CSV
is plaintext by construction, lossy by omission, and carries no
integrity: nothing in it says which rows were meant to be there, so a
truncated import looks exactly like a complete one.

The same gap showed up inside LogicSRC. `logicsrc credentials` moves
.env secrets and SSH keys through end-to-end-encrypted team vaults, but
it can only model a key/value pair. A card, a passport, a login with a
TOTP seed, or an OAuth account with a refresh token are all things
people already keep in a vault, and none of them are a key/value pair.

OpenCreds defines three things: the item, the vault, and the database.

- Six item types (login, card, identity, note, key, account) as one
  record with a type and a named field group, so everything the user
  typed lives in a single encrypted blob. Codes 1-4 match MarkSyncr's
  deployed vault and are not renumbered; compatibility is cheaper than
  elegance.
- AES-256-GCM over that record with the item id bound as AAD. Without
  it, anyone with storage write access could move a low-value login's
  ciphertext into a high-value row and watch what the user does next.
- A key hierarchy where the user key is random, not derived, so a
  password change re-wraps 32 bytes rather than re-encrypting a vault.
  The auth hash comes out of a different HKDF label than the wrap key,
  which is what lets it reach a server at all.
- A portable .opencreds file, encrypted by default, whose header is the
  AAD over the payload -- so the manifest is authenticated by the same
  tag as the data and a truncated import fails rather than reporting
  success. The plaintext form exists because people move to products
  that read nothing else; it is opt-in, confirmed, 0600, and labelled
  "protected": false in its own header.

Namespaces are carried as data, not fixed by the spec: labels are
compiled into every ciphertext a vault has written, so editing one does
not migrate a vault, it makes it undecryptable. MarkSyncr's deployed
vault is conformant by declaring `marksyncr`.

Ships: prd/0004, nine spec pages under docs/opencreds/, six JSON
Schemas, the @logicsrc/opencreds reference implementation with CSV
importers for five products, `logicsrc vault` and the standalone
`opencreds` binary, and the spec page at logicsrc.com/opencreds.

`vault` rather than `creds` because `creds` is already an alias of
`logicsrc credentials`, and the two are different: one moves a pair
between providers, the other stores a record.

@logicsrc/validators now registers every schema by $id before
compiling, so the database schema can $ref the item and manifest
schemas rather than restating them.

120 tests, including CLI end-to-end coverage of the masking rules,
exit codes, and the manifest-mismatch path.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01QRQrfuwuYKKV5UB9kLHuX5

* Make the OpenCreds conformance claim executable

The conformance page described a fixture suite and an `opencreds
conformance` command that did not exist. A specification that documents
a conformance surface it cannot run is a specification nobody can hold
to, including us.

`opencreds conformance` now runs the requirement list as code -- one
check per C-number, carrying its own id and level -- and emits the
report shape the spec publishes. It exits 2 when a MUST does not pass,
so it can gate CI directly. The reference implementation reports 29
passed, 0 failed, 1 skipped; the skip is C19, because key management for
the team profile lives in @logicsrc/plugin-credential-sharing rather
than in this package, and a skipped MAY does not affect conformance.

Fixtures are generated (`--emit-fixtures <dir>`) rather than
hand-written. A vector produced by an implementation and then verified
by it is worth more than a JSON file someone typed: the typed file
drifts silently when the format moves, and the generated one cannot.
Fourteen files, including an invalid/ set every conforming reader must
reject -- a wrong field group, a weak KDF, an unregistered namespace, a
short payload and a tampered manifest.

The CLI requirements stay with the end-to-end tests that drive the real
binary through a child process; a command cannot meaningfully check its
own exit codes, and a masked value that is only masked in the library is
not masked.

conformance.md and cli.md now describe what ships.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01QRQrfuwuYKKV5UB9kLHuX5

* Add @logicsrc/opencreds to the lockfile

`npm ci` refuses a lockfile that does not match package.json, and the
new workspace package plus the CLI's dependency on it were never
recorded: the worktree was bootstrapped by hardlinking node_modules
rather than installing, so npm was never asked to update the lock.

Adds the workspace link and the package entry. No dependency versions
move.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01QRQrfuwuYKKV5UB9kLHuX5

* Register PRD 0004, and stop the fixtures looking like real secrets

Two CI failures, both mine.

`prd/README.md` is generated by `logicsrc prd index --write` and the
scaffold test asserts it is current, so adding a PRD without
regenerating it leaves the repo's own conformance check failing.
Regenerated. The MCP test asserts the next free PRD id against the live
prd/ directory — its comment says it advances with every PRD added — so
it moves to 0005.

ThreatCrush flagged three of the example strings: a PEM header in the
item-model docs and in the conformance fixture, and an `sk_live_`
prefixed token. All placeholders, none real, but the finding is the
scanner working. A fixture only has to exercise the field, and a
real-looking private key header or live-key prefix sitting in the tree
trains both the scanner and the people reading its output to shrug at
exactly the shape that matters. Replaced with obvious placeholders
rather than suppressing the rule.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01QRQrfuwuYKKV5UB9kLHuX5

---------

Co-authored-by: Claude Opus 5 (1M context) <noreply@anthropic.com>

docs/opencreds/faq.md

@@ -0,0 +1,91 @@
+# OpenCreds FAQ
+
+### Why not just use the Bitwarden JSON export?
+
+It is the closest thing that exists, and it is a product's export format rather
+than a specification: undocumented, versioned by the product, plaintext-only in
+practice, and with no integrity check. OpenCreds keeps the parts that work — the
+item-with-a-type-group shape, the type codes — and adds the parts that are
+missing: an encrypted form as the default, an authenticated manifest, a declared
+crypto construction, published schemas and a conformance suite.
+
+The type codes 1–4 are deliberately the same. Compatibility is cheaper than
+elegance.
+
+### Why is there a plaintext form at all?
+
+Because people move *to* products that read nothing else, and a format that
+refuses to express that gets worked around with a script that is worse — no
+warning, no file mode, no label. Specifying it means it can be made loud: an
+explicit flag, a confirmation, `protected: false` in the header, and an owner-only
+file mode.
+
+### Why PBKDF2 rather than Argon2id?
+
+Argon2id is better and needs WASM in a browser, which means adding
+`wasm-unsafe-eval` to an extension's content security policy. That is a real cost
+paid by every user of a product to benefit the KDF. The parameters are carried
+per vault specifically so the switch is a migration later rather than a break
+now, and `argon2id` is already a registered value.
+
+### Why is `namespace` a property instead of a constant?
+
+Because MarkSyncr's vault shipped first, with `marksyncr:vault:*` labels baked
+into the additional authenticated data of every ciphertext it has written.
+Changing a label does not migrate a vault; it makes it undecryptable. Carrying
+the prefix as data is what lets a deployed vault be conformant without
+re-encrypting a single item. New vaults use `opencreds`.
+
+### Why is an `account` not a `login`?
+
+A login is what a person types at a sign-in form. An account is what a machine
+presents to an API. They expire differently, they are revoked differently, and
+they are rotated by different actors. Conflating them is how a rotated refresh
+token ends up in a password history array, and how an expiry date ends up in a
+notes field.
+
+### Can I keep `.env` secrets in an OpenCreds vault?
+
+Yes — that is what `key` items with `keyType: "env"` are. The variable name is
+the item `name` and the secret is `key.value`. `logicsrc credentials` moves those
+values *between providers*; OpenCreds is what one looks like when it is stored
+rather than moved.
+
+### Does this replace `logicsrc credentials`?
+
+No. Credential Sharing is a sync spec: providers, plans, diffs, dry runs,
+rollback and audit. OpenCreds is a record and a file. They meet at the `key`
+item — a synced `.env` entry, stored — and at the `team` profile, which is the
+credential-sharing key scheme applied to a vault of items.
+
+### What happens if two devices edit the same item?
+
+The specification does not say, because it does not specify storage. The
+reference implementation and both Profullstack products store one row per item
+with a monotonic revision, so a client that writes with a stale revision is
+rejected rather than overwriting. That is a recommendation, not a requirement.
+
+### Why cap password history at twenty?
+
+The item is one blob, rewritten in full on every save. An uncapped history array
+grows that blob without bound, and the growth is invisible until a vault sync
+starts timing out. Twenty entries is more history than anyone consults.
+
+### Can I import a vault without the passphrase, just to see what is in it?
+
+You can see the header: version, namespace, export time, generator, and the
+manifest — item count, counts by type, folder count. That is enough for a
+preview and it is authenticated, so it cannot be lied about. Nothing else is
+readable, which is the point.
+
+### Is there a hosted OpenCreds service?
+
+No, and the specification does not describe one. A conforming vault is a file
+and a key. Products built on it may be hosted; the standard is not.
+
+### How do I claim conformance?
+
+Run `opencreds conformance` against the published fixtures, pass every MUST, and
+say which profile and namespace you implement. The suite is in
+`packages/opencreds/fixtures/` and ships in the published package, so nobody has
+to read our source to verify their own implementation.